Is Broadband Max working?

[#1]

My broadband speed is slow, usually around 500kbps which in the main is due to my distance from the exchange. When I elected to go onto Broadband Max rather than a fixed line speed I did see an improvement in speed albeit only a bit but I used to regularly get around 700kbps. Not much you say but for me a welcome change. Since the outrage at Bradwell Abbey some weeks back and the problem that Plusnet suffered a couple of weekends ago my speed has only occasionally gone above 500kbps. Now I am about to change over to 21st Century in the next few days so hopefully that might lead to an improvement but Broadband Max seems quite fragile if you generally have a slower connection. Can anyone throw any light on the reasons for this?
David

[#2]

It's basically down to the limits of copper wiring. The longer the line is, the more interference it generates and therefore the noisier the line. The connection will therefore have to be slower in order to remain stable and not drop all the time.

[#3]

If you post your router stats (sync speed, noise margin and attenuation) we can say whether your speeds look right.

[#4]

These are my stats. I think my point was, why does line speed occassionally  go up but is never maintained when in the past it would for as long as a couple of weeks.
David
System Up Time 79:41:40
Port Status TxPkts RxPkts Collisions Tx B/s Rx B/s Up Time
WAN PPPoA 822217 1150303 0 596 14433 29:43:56
LAN 10M/100M 75382 0 0 183 0 79:41:36
WLAN 11M/54M/130M 3436800 2529720 0 1294 939 79:41:25

ADSL Link Downstream Upstream
Connection Speed 704 kbps 448 kbps
Line Attenuation 62.0 db 31.0 db
Noise Margin 8.6 db 17.0 db

[#5]

That doesn't look to be a good sync speed for your attenuation.
Do the stats look any better from the test socket in side the master socket with no phone attached?

[#6]

I rebooted the modem, power off for 10 minutes and removed the phone line from the filter which is a new ADLS Nation filter as recommended here. I have pasted the new stats below and as can be seen the sync rate has doubled but there has been no increase in speed. When I reinstated the phone line there was no noticeable change.
David
System Up Time 00:16:00
Port Status TxPkts RxPkts Collisions Tx B/s Rx B/s Up Time
WAN PPPoA 2025 2102 0 3903 7741 00:03:56
LAN 10M/100M 413 0 0 63 0 00:15:56
WLAN 11M/54M/130M 9647 9002 0 9163 4446 00:15:45

ADSL Link Downstream Upstream
Connection Speed 1408 kbps 448 kbps
Line Attenuation 62.0 db 31.0 db
Noise Margin 9.1 db 17.0 db

[#7]

and double down load synch speed