Randon daily disconnections

[#1]

For a while now, I have had random but daily disconnections, most of which have lasted 2.1/2 - 3 minutes and reconnected with no intervention from me, and usually with no effect on my speed or any statistics I can pick up easily from my router (DG834gv5). However, when this happened last night, I was actually using the laptop, noticed the drop and thought it was about time I tried to understand what was going on - so I grabbed the following data - which means very little to me, but did make me wonder.
The main things that grabbed my attention were the downstream SNR - at the lowest I've ever seen it while still being able to access sites, and the connection speed - which was around 1000mbps higher than my IP profile according to the BT speedtester.
Statistics below all recorded inside half an hour of the event:
(1) BT Speedtest
1. Best Effort Test: -provides background information.
Download  Speed
5.42 Mbps
0 Mbps 7.15 Mbps
Max Achievable Speed
Download speedachieved during the test was - 5.42 Mbps
For your connection, the acceptable range of speeds is 2 Mbps-7.15 Mbps.
IP Profile for your line is - 5.8 Mbps
2. Upstream Test: -provides background information.
Upload Speed
0.56 Mbps
0 Mbps 0.83 Mbps
Max Achievable Speed
Upload speed achieved during the test was - 0.56Mbps
Additional Information:
Upstream Rate IP profile on your line is - 0.83 Mbps
(2)Line Speed - Not a lot of help
High-speed Broadband
Estimated line speed
Not recorded (service activated before we introduced estimates).
Current line speed:
    21 Mb
Your estimated line speed
(3)Router stats
Port  Status  TxPkts  RxPkts  Collisions  Tx B/s  Rx B/s  Up Time 
WAN  PPPoA  2326  2221  0  138  443  00:56:46 
LAN  100M/Full  45281  22328  0  47  6  8 days 11:13:25 
WLAN 11M/54M 1001105 876754 0 1091 201 8 days 11:13:42
ADSL Link Downstream Upstream
Connection Speed 6579 kbps 720 kbps
Line Attenuation 51.0 db 24.0 db
Noise Margin 3.05 db 7.0 db

(4) Router Logs
[Admin login] from source 192.168.0.3, Wednesday, Jan 01,2003 00:56:10
[Admin login failure] from source 192.168.0.3, Wednesday, Jan 01,2003 00:56:06
[Admin login] from source 192.168.0.3, Wednesday, Jan 01,2003 00:56:05
[Admin login failure] from source 192.168.0.3, Wednesday, Jan 01,2003 00:55:58
[Admin login] from source 192.168.0.3, Wednesday, Jan 01,2003 00:55:57
[Admin login failure] from source 192.168.0.3, Wednesday, Jan 01,2003 00:55:47
[Admin login] from source 192.168.0.3, Wednesday, Jan 01,2003 00:55:46
[Internet connected] IP address: 87.114.xx.xxx, Wednesday, Jan 01,2003 00:00:17
[Internet disconnected] Wednesday, Jan 01,2003 00:00:00
[UPnP set event: Public_UPNP_C3] from source 192.168.0.3, Monday, Jun 04,2012 15:24:54
[Admin login] from source 192.168.0.3, Monday, Jun 04,2012 13:40:28
[Admin login failure] from source 192.168.0.3, Monday, Jun 04,2012 13:40:14
[Admin login] from source 192.168.0.3, Monday, Jun 04,2012 13:40:14
[Admin login failure] from source 192.168.0.3, Monday, Jun 04,2012 13:40:07
[Admin login] from source 192.168.0.3, Monday, Jun 04,2012 13:40:06
[DHCP IP: (192.168.0.3)] to MAC address 90:A4:DE:29:59:71, Monday, Jun 04,2012 13:37:56
[DHCP IP: (192.168.0.2)] to MAC address 00:10:DC:C5:15:C8, Monday, Jun 04,2012 09:10:06
[DHCP IP: (192.168.0.2)] to MAC address 00:10:DC:C5:15:C8, Monday, Jun 04,2012 08:54:19
[Admin login] from source 192.168.0.3, Monday, Jun 04,2012 05:55:50
[Admin login failure] from source 192.168.0.3, Monday, Jun 04,2012 05:55:46
[Admin login] from source 192.168.0.3, Monday, Jun 04,2012 05:54:03
[Admin login failure] from source 192.168.0.3, Monday, Jun 04,2012 05:53:57
[Admin login] from source 192.168.0.3, Monday, Jun 04,2012 05:53:56
[DHCP IP: (192.168.0.3)] to MAC address 90:A4:DE:29:59:71, Monday, Jun 04,2012 05:05:13
[Internet connected] IP address: 91.125.xxx.xx, Monday, Jun 04,2012 00:49:43
[Internet disconnected] Monday, Jun 04,2012 00:48:32
[DHCP IP: (192.168.0.3)] to MAC address 90:A4:DE:29:59:71, Sunday, Jun 03,2012 18:42:09
[Admin login] from source 192.168.0.3, Sunday, Jun 03,2012 17:11:06
[Admin login failure] from source 192.168.0.3, Sunday, Jun 03,2012 17:10:58
[Admin login] from source 192.168.0.3, Sunday, Jun 03,2012 17:10:57
[Internet connected] IP address: 87.112.114.240, Sunday, Jun 03,2012 11:49:20
[Internet disconnected] Sunday, Jun 03,2012 11:47:05
[Admin login] from source 192.168.0.3, Sunday, Jun 03,2012 07:51:05
[Admin login failure] from source 192.168.0.3, Sunday, Jun 03,2012 07:51:00
[Admin login failure] from source 192.168.0.3, Sunday, Jun 03,2012 07:49:33
[Admin login] from source 192.168.0.3, Sunday, Jun 03,2012 07:49:33
[Admin login failure] from source 192.168.0.3, Sunday, Jun 03,2012 07:49:32
[Admin login] from source 192.168.0.3, Sunday, Jun 03,2012 07:49:32
[DHCP IP: (192.168.0.3)] to MAC address 90:A4:DE:29:59:71, Sunday, Jun 03,2012 06:42:09
[Internet connected] IP address: 84.51.191.16, Sunday, Jun 03,2012 03:24:51
[Internet disconnected] Sunday, Jun 03,2012 03:20:02
[UPnP set event: Public_UPNP_C5] from source 192.168.0.3, Saturday, Jun 02,2012 17:36:21
[UPnP set event: Public_UPNP_C5] from source 192.168.0.3, Saturday, Jun 02,2012 17:34:27
[UPnP set event: Public_UPNP_C5] from source 192.168.0.3, Saturday, Jun 02,2012 17:31:57
[UPnP set event: Public_UPNP_C5] from source 192.168.0.3, Saturday, Jun 02,2012 17:18:53
[Admin login] from source 192.168.0.3, Saturday, Jun 02,2012 17:17:52
[Admin login failure] from source 192.168.0.3, Saturday, Jun 02,2012 17:17:47
[UPnP set event: Public_UPNP_C5] from source 192.168.0.3, Saturday, Jun 02,2012 17:16:54
[Admin login] from source 192.168.0.3, Saturday, Jun 02,2012 17:16:03
[Admin login failure] from source 192.168.0.3, Saturday, Jun 02,2012 17:15:56
[Admin login] from source 192.168.0.3, Saturday, Jun 02,2012 17:15:56
Then many  lines as this:
[UPnP set event: Public_UPNP_C3] from source 192.168.0.3, Saturday, Jun 02,2012 04:41:16
[DHCP IP: (192.168.0.3)] to MAC address 90:A4:DE:29:59:71, Saturday, Jun 02,2012 04:40:12
[Admin login] from source 192.168.0.3, Friday, Jun 01,2012 19:33:16
[Admin login failure] from source 192.168.0.3, Friday, Jun 01,2012 19:33:11
[Admin login] from source 192.168.0.3, Friday, Jun 01,2012 19:31:20
[Admin login failure] from source 192.168.0.3, Friday, Jun 01,2012 19:26:53
[Admin login] from source 192.168.0.3, Friday, Jun 01,2012 19:26:44
[Admin login failure] from source 192.168.0.3, Friday, Jun 01,2012 19:26:37
[Admin login] from source 192.168.0.3, Friday, Jun 01,2012 19:26:37
[Internet connected] IP address: 87.115.173.252, Friday, Jun 01,2012 19:26:27
[Admin login] from source 192.168.0.3, Friday, Jun 01,2012 19:24:29
[Admin login failure] from source 192.168.0.3, Friday, Jun 01,2012 19:24:24
[Admin login] from source 192.168.0.3, Friday, Jun 01,2012 19:24:03
[Admin login failure] from source 192.168.0.3, Friday, Jun 01,2012 19:24:00
[Admin login] from source 192.168.0.3, Friday, Jun 01,2012 19:23:59
[Internet disconnected] Friday, Jun 01,2012 19:23:42
[Admin login failure] from source 192.168.0.3, Friday, Jun 01,2012 19:23:27
[Admin login] from source 192.168.0.3, Friday, Jun 01,2012 19:23:26
[Admin login] from source 192.168.0.3, Friday, Jun 01,2012 18:21:30
[Admin login failure] from source 192.168.0.3, Friday, Jun 01,2012 18:21:23
[Admin login] from source 192.168.0.3, Friday, Jun 01,2012 18:21:22
[Admin login] from source 192.168.0.3, Friday, Jun 01,2012 18:14:30
[Admin login failure] from source 192.168.0.3, Friday, Jun 01,2012 18:14:26
[Admin login] from source 192.168.0.3, Friday, Jun 01,2012 18:13:24
[Admin login failure] from source 192.168.0.3, Friday, Jun 01,2012 18:13:18
[Admin login] from source 192.168.0.3, Friday, Jun 01,2012 18:13:17
[DHCP IP: (192.168.0.3)] to MAC address 90:A4:DE:29:59:71, Friday, Jun 01,2012 17:55:54
[DHCP IP: (192.168.0.4)] to MAC address F0:A2:25:3A:2F:24, Friday, Jun 01,2012 17:33:29
[DHCP IP: (192.168.0.4)] to MAC address F0:A2:25:3A:2F:24, Friday, Jun 01,2012 17:30:21
[Admin login] from source 192.168.0.3, Friday, Jun 01,2012 09:25:21
[Admin login failure] from source 192.168.0.3, Friday, Jun 01,2012 09:25:16
[Admin login] from source 192.168.0.3, Friday, Jun 01,2012 09:25:08
[Admin login failure] from source 192.168.0.3, Friday, Jun 01,2012 09:25:08
[Admin login] from source 192.168.0.3, Friday, Jun 01,2012 09:25:07
[Admin login] from source 192.168.0.3, Friday, Jun 01,2012 06:06:54
[Admin login failure] from source 192.168.0.3, Friday, Jun 01,2012 06:06:50
[Admin login] from source 192.168.0.3, Friday, Jun 01,2012 06:06:49
[Admin login failure] from source 192.168.0.3, Friday, Jun 01,2012 06:06:37
[Admin login] from source 192.168.0.3, Friday, Jun 01,2012 06:06:36
[DHCP IP: (192.168.0.3)] to MAC address 90:A4:DE:29:59:71, Friday, Jun 01,2012 05:55:54
[Admin login] from source 192.168.0.3, Thursday, May 31,2012 17:37:01
[Admin login failure] from source 192.168.0.3, Thursday, May 31,2012 17:36:56
[Admin login] from source 192.168.0.3, Thursday, May 31,2012 17:35:24
[Admin login failure] from source 192.168.0.3, Thursday, May 31,2012 17:35:21
[Admin login] from source 192.168.0.3, Thursday, May 31,2012 17:35:20
[Admin login] from source 192.168.0.3, Thursday, May 31,2012 17:17:29
[Admin login failure] from source 192.168.0.3, Thursday, May 31,2012 17:17:22
[Internet connected] IP address: 91.125.221.90, Thursday, May 31,2012 17:16:57
[Admin login] from source 192.168.0.3, Thursday, May 31,2012 17:16:23
[Admin login failure] from source 192.168.0.3, Thursday, May 31,2012 17:16:16
[Admin login] from source 192.168.0.3, Thursday, May 31,2012 17:16:15
[Internet disconnected] Thursday, May 31,2012 17:14:58
[DHCP IP: (192.168.0.3)] to MAC address 90:A4:DE:29:59:71, Thursday, May 31,2012 16:59:26
[Admin login] from source 192.168.0.3, Thursday, May 31,2012 11:36:42
[Admin login failure] from source 192.168.0.3, Thursday, May 31,2012 11:36:37
[Admin login] from source 192.168.0.3, Thursday, May 31,2012 11:35:29
[Admin login failure] from source 192.168.0.3, Thursday, May 31,2012 11:35:23
[Admin login] from source 192.168.0.3, Thursday, May 31,2012 11:35:22
[Admin login] from source 192.168.0.3, Wednesday, Jan 01,2003 04:20:57
[Admin login failure] from source 192.168.0.3, Wednesday, Jan 01,2003 04:20:47
[Admin login] from source 192.168.0.3, Wednesday, Jan 01,2003 04:20:37
[Admin login failure] from source 192.168.0.3, Wednesday, Jan 01,2003 04:20:32
[Admin login] from source 192.168.0.3, Wednesday, Jan 01,2003 04:20:32
[Admin login failure] from source 192.168.0.3, Wednesday, Jan 01,2003 04:20:25
[Admin login] from source 192.168.0.3, Wednesday, Jan 01,2003 04:20:24
[DHCP IP: (192.168.0.3)] to MAC address 90:A4:DE:29:59:71, Wednesday, Jan 01,2003 03:42:09
[Internet connected] IP address: 84.93.180.227, Wednesday, Jan 01,2003 00:01:35
[Internet disconnected] Wednesday, Jan 01,2003 00:00:00
[DHCP IP: (192.168.0.3)] to MAC address 90:A4:DE:29:59:71, Wednesday, May 30,2012 16:31:02
[Admin login] from source 192.168.0.3, Wednesday, May 30,2012 13:38:21
[Admin login failure] from source 192.168.0.3, Wednesday, May 30,2012 13:38:16
[Admin login] from source 192.168.0.3, Wednesday, May 30,2012 13:38:16
[Admin login failure] from source 192.168.0.3, Wednesday, May 30,2012 13:38:02
[Admin login] from source 192.168.0.3, Wednesday, May 30,2012 13:38:02
[Admin login failure] from source 192.168.0.3, Wednesday, May 30,2012 13:37:56
[Admin login] from source 192.168.0.3, Wednesday, May 30,2012 13:37:55
[DHCP IP: (192.168.0.2)] to MAC address 00:10:DC:C5:15:C8, Wednesday, May 30,2012 05:57:05
[Admin login] from source 192.168.0.3, Wednesday, May 30,2012 05:16:37
[Admin login failure] from source 192.168.0.3, Wednesday, May 30,2012 05:16:33
[Admin login] from source 192.168.0.3, Wednesday, May 30,2012 05:16:32
[Admin login failure] from source 192.168.0.3, Wednesday, May 30,2012 05:16:27
[Admin login] from source 192.168.0.3, Wednesday, May 30,2012 05:16:26
[DHCP IP: (192.168.0.3)] to MAC address 90:A4:DE:29:59:71, Wednesday, May 30,2012 04:31:01
[Internet connected] IP address: 87.112.103.22, Tuesday, May 29,2012 21:28:37
[Internet disconnected] Tuesday, May 29,2012 21:27:30
[Admin login] from source 192.168.0.3, Tuesday, May 29,2012 17:44:44
[Admin login failure] from source 192.168.0.3, Tuesday, May 29,2012 17:44:25
[Admin login] from source 192.168.0.3, Tuesday, May 29,2012 17:44:24
[Admin login failure] from source 192.168.0.3, Tuesday, May 29,2012 17:43:48
[Admin login] from source 192.168.0.3, Tuesday, May 29,2012 17:43:48
[DHCP IP: (192.168.0.3)] to MAC address 90:A4:DE:29:59:71, Tuesday, May 29,2012 16:19:30
[Admin login] from source 192.168.0.3, Tuesday, May 29,2012 16:15:20
[Admin login failure] from source 192.168.0.3, Tuesday, May 29,2012 16:15:00
[Admin login] from source 192.168.0.3, Tuesday, May 29,2012 16:14:45
[Admin login failure] from source 192.168.0.3, Tuesday, May 29,2012 16:14:45
[Admin login] from source 192.168.0.3, Tuesday, May 29,2012 16:14:44
[Admin login failure] from source 192.168.0.3, Tuesday, May 29,2012 16:13:12
[Admin login] from source 192.168.0.3, Tuesday, May 29,2012 16:13:12
[Admin login] from source 192.168.0.3, Tuesday, May 29,2012 16:12:10
[Admin login failure] from source 192.168.0.3, Tuesday, May 29,2012 16:11:53
[Admin login] from source 192.168.0.3, Tuesday, May 29,2012 16:10:23
[Admin login failure] from source 192.168.0.3, Tuesday, May 29,2012 16:10:06
[Admin login] from source 192.168.0.3, Tuesday, May 29,2012 16:09:34
[Admin login failure] from source 192.168.0.3, Tuesday, May 29,2012 16:09:33
[Admin login] from source 192.168.0.3, Tuesday, May 29,2012 16:09:33
[Admin login] from source 192.168.0.3, Tuesday, May 29,2012 05:01:57
[Admin login failure] from source 192.168.0.3, Tuesday, May 29,2012 05:01:53
[Admin login] from source 192.168.0.3, Tuesday, May 29,2012 05:01:52
[Admin login failure] from source 192.168.0.3, Tuesday, May 29,2012 05:01:46
[Admin login] from source 192.168.0.3, Tuesday, May 29,2012 05:00:53
[Admin login failure] from source 192.168.0.3, Tuesday, May 29,2012 05:00:47
[Admin login] from source 192.168.0.3, Tuesday, May 29,2012 05:00:46
[DHCP IP: (192.168.0.3)] to MAC address 90:A4:DE:29:59:71, Tuesday, May 29,2012 04:19:29
[UPnP set event: Public_UPNP_C3] from source 192.168.0.3, Monday, May 28,2012 20:17:02
[Admin login] from source 192.168.0.3, Monday, May 28,2012 20:12:21
[Admin login failure] from source 192.168.0.3, Monday, May 28,2012 20:12:17
[Admin login] from source 192.168.0.3, Monday, May 28,2012 20:07:44
Then more of these:
[UPnP set event: Public_UPNP_C3] from source 192.168.0.3, Monday, May 28,2012 19:03:39
[Admin login] from source 192.168.0.3, Monday, May 28,2012 17:34:32
[Admin login failure] from source 192.168.0.3, Monday, May 28,2012 17:34:24
[Internet connected] IP address: 91.125.123.188, Monday, May 28,2012 17:33:42
[Admin login] from source 192.168.0.3, Monday, May 28,2012 17:33:00
[Admin login failure] from source 192.168.0.3, Monday, May 28,2012 17:32:53
[Admin login] from source 192.168.0.3, Monday, May 28,2012 17:32:52
[Internet disconnected] Monday, May 28,2012 17:31:51
[DHCP IP: (192.168.0.3)] to MAC address 90:A4:DE:29:59:71, Monday, May 28,2012 17:05:42
[Admin login] from source 192.168.0.3, Monday, May 28,2012 17:03:56
[Admin login failure] from source 192.168.0.3, Monday, May 28,2012 17:03:49
[Admin login] from source 192.168.0.3, Monday, May 28,2012 17:03:48
[Admin login failure] from source 192.168.0.3, Monday, May 28,2012 17:03:41
[Admin login] from source 192.168.0.3, Monday, May 28,2012 17:03:41
[Admin login] from source 192.168.0.3, Monday, May 28,2012 16:32:35
[Admin login failure] from source 192.168.0.3, Monday, May 28,2012 16:32:30
[Admin login] from source 192.168.0.3, Monday, May 28,2012 16:32:30
[Admin login failure] from source 192.168.0.3, Monday, May 28,2012 16:32:22
[Admin login] from source 192.168.0.3, Monday, May 28,2012 16:32:21
[Admin login] from source 192.168.0.3, Monday, May 28,2012 07:20:30
[Admin login failure] from source 192.168.0.3, Monday, May 28,2012 07:20:17
[Admin login] from source 192.168.0.3, Monday, May 28,2012 07:19:28
[Admin login failure] from source 192.168.0.3, Monday, May 28,2012 07:19:23
[Admin login] from source 192.168.0.3, Monday, May 28,2012 07:19:22
[Admin login failure] from source 192.168.0.3, Monday, May 28,2012 07:19:15
[Admin login] from source 192.168.0.3, Monday, May 28,2012 07:19:14
[DHCP IP: (192.168.0.3)] to MAC address 90:A4:DE:29:59:71, Monday, May 28,2012 05:05:41
[UPnP set event: Public_UPNP_C3] from source 192.168.0.3, Sunday, May 27,2012 14:36:06
[Internet connected] IP address: 46.208.179.176, Sunday, May 27,2012 14:35:24
]And then I had another (rapid) disconnect/reconnect this afternoon with the resulting routerstats:
Port  Status  TxPkts  RxPkts  Collisions  Tx B/s  Rx B/s  Up Time 
WAN  PPPoA  601  400  0  438  1126  00:03:41 
LAN  100M/Full  45281  22328  0  43  6  9 days 07:03:12 
WLAN 11M/54M 1118047 975748 0 1128 207 9 days 07:03:29
ADSL Link Downstream Upstream
Connection Speed 4011 kbps 736 kbps
Line Attenuation 50.5 db 24.0 db
Noise Margin 10.25 db 6.5 db

Can anyone, after wading through that lot, give me any clues?

[#2]

Sounds like you have a bad dropping connection.
When the Plusnet staff are in tomorrow they can check you connection history, but to help avoid the Target SNRM being raised and resultant lower speed, if you need to swap things around follow this method -
Use this Disconnect method -
Do a Disconnect of your PPP Internet session with the ISP - you need to login to the modem/router interface and look for the Disconnect button to click on. On the Thomson modem/routers you will typically find it in the box marked Internet as shown here. Now wait a few minutes, power down. Then wait 10 minutes (during this time swap any filters, modem/router, connect to test socket, etc. - it doesn't matter if you take longer than 10 minutes) and then power up again (You may need to login to the modem/router and click on Connect to re-establish the PPP Internet session). Check the stats immediately (The Noise Margin [SNRM] shown is usually the current Target Noise Margin).
I usually recommend you do this no more than 5 times in an hour, and then leave it alone for the rest of the day. 
Remember the reason for this procedure is to help prevent the exchange DLM from thinking you have a dropping
connection. (But it's no guarantee!).
You can use the Disconnect/Connect (without a power down) to Gateway hop.
When you connect to the test socket, you need to be looking at the sync speed with the exchange (the Connection speed - 4011 in the stats at the end of your post) if it's significantly better in the test socket you may have an issue with your fixed extension wiring if you have any. Try the test socket in daylight hours, noise levels tend to be lower, so speeds better.
The other thing to check is, can you hear any audible noise on your line when using the phone - if so check with a corded phone in the test socket and if still present report a phone line fault to your line rental provider - don't mention the broadband otherwise you get the run around.

[#3]

Cheers, Anotherone - that's about what I thought, but running it past someone with more knowledge than myself seemed a good idea.
The only thing that makes me wonder if it's something outside my system is the routerstats at (3) - they don't look possible given the BT test run at the time - or am I missing something?
I'll attempt to do a connection to the test socket sometime tomorrow, but can't say when - I've got my mum in hospital after a stroke, so I'm kind of here/not here, if that makes sense?

[#4]

Totally, you look after your Mum, this can wait.

[#5]

Update
My connection has stayed up for nearly two days (something of a record recently ) and I'm a little reluctant to disturb it - I can live with the current situation, although I would like a bit more speed and lower SNR.
In anticipation of someone on the DCT picking up on the thread however, and suggesting I try another router/change filters &c,  i am looking at this router  http://www.7dayshop.com/catalog/product_info.php?cPath=777_9&products_id=113814
Any comments, suggestions?
Help so far much appreciated

[#6]

Hi jab1,
the line is looking a lot more stable and the current SNR is 3dB with a sync rate of 4008
Jojo

[#7]

Thanks JoJo
Below is what my router is saying  - downstream SNR says 10.5 db 
System Up Time 11 days 08:22:08
Port  Status  TxPkts  RxPkts  Collisions  Tx B/s  Rx B/s  Up Time 
WAN  PPPoA  162033  188731  0  159  918  2 days 01:22:20 
LAN  100M/Full  45281  22328  0  35  5  11 days 08:21:51 
WLAN 11M/54M 1350831 1181928 0 1103 206 11 days 08:22:08

ADSL Link Downstream Upstream
Connection Speed 4011 kbps 736 kbps
Line Attenuation 50.5 db 24.0 db
Noise Margin 10.05 db 7.0 db

[#8]

Hi jab1,
I can only conclude that the router is misreporting the SNR. I've checked on two systems and it's showing as ~3dB I do think it could be a bit better though. If you're using the test socket and you've changed filters I'd suggest raising a fault.
Jojo

[#9]

Thanks Jojo. At he moment, I haven't changed anything - I believe in the maxim 'If it's working, don't disturb it'
Having said that, though, seeing as I'm more inclined to trust your equipment than mine, I will reboot the router sometime today, and take the opportunity to change the filters.
Sorry I didn't make it clear that atm, the router is still plugged in to the upstairs office phone point - plugging in to the test socket involves re-organising  furniture downstairs, and as I've said, with my mum in hospital, things like that are taking a bit of a back seat.
Out of interest, I had another disconnection early this morning (snipped router log below), but router statistics doesn't reflect it.  
Admin login] from source 192.168.0.3, Friday, Jun 08,2012 06:04:20
[DHCP IP: (192.168.0.3)] to MAC address 90:A4:DE:29:59:71, Friday, Jun 08,2012 05:43:29
[Internet connected] IP address: 146.66.xx.xxx, Friday, Jun 08,2012 01:27:01
[Internet disconnected] Friday, Jun 08,2012 01:25:54
NOTE: Times are BST

[#10]

That loss of Internet PPP session could be BT maintenance.
As for another modem/router, I've no idea how good or reliable that one you are looking at may be, but as long as it can provide ADSL line stats preferably with reported errors such as CRC/HEC/ES etc, then at that price, well go for it. A least you'll have another to compare with.

[#11]

Ooops - forgot about the BT thing
Think I may go for the router - because it's a 'B' grade, theres a 30 day no-quibble return on it, so if I don't like it, I can return it.

[#12]

Update:
As I've had no further disconnections and everything is running fine, I don't think I'll be changing anything at the moment, but I now have 2 brand new filters and the router I linked to earlier in this thread, and at the first sign of trouble, I'll change 'em all.
As a point of interest, why has my connection stabalised at 4008, when prior to the start of my problem, I was getting a figure closer to 5600? Not a problem - for what I use, this speed is OK, although slightly hiher would be nice. 

[#13]

I'd guess because your Target Noise Margin has risen because of the drops you appeared to have had previously, that based on the last posted ADSL lInk stats. If the connection is stable, Plusnet would probably do an SNR reset for you.

[#14]

Thanks for the reply Anotherone, but according to Jojo (see replies #5 & #7) my SNR is 3dB, so would a reset achieve anything?

PS - do you ever go to bed? 

[#15]

I've just run a few sequential line tests and some show me a downstream SNR of 3db. I can see a 7 hour connection and prior to that 6 days so I doubt there's anything further that needs to be done.
let us know if you start to have any issues again.