Another terrible upload speeds and poor stability

[#1]

Like wytco0, I've been having trouble with my broadband.  Variable download speeds (3 - 6Mb/s) but, more importantly, really poor upload speeds (40 - 380 Kb/s, but most frequently 90-160 Kb/s).  The wireless signal seems to be fine, as I also get these results if I'm plugged into the router with a cable.
I've been with Plusnet since September and March is the first month that I've noticed sustained problems, in that before there might be a day where things weren't great but in March it's been really poor for the whole month.  The router has kicked us off the internet more frequently (perhaps twice in the previous 5 months, ~4 times this month including twice today).  Since that most recent reset, the Speedtest stats are much better (5-6 Mb/s download & ~350 Kb/s upload).  However, it was also much better after the previous reset and that degraded pretty quickly, so I'm not expecting it to last.
As with wytco0, upload speed is important to me.  The main differences between us are I'm using the Plusnet supplied TG585v8 and I'm not a new customer (i.e. everything has been fine until this month).  Data points: no new devices plugged in; our router is plugged into the socket where the telephone wiring enters the house; both before and during March, our download speed has usually been good (for where we are) at 5-6 Mb/s, but it has dropped to 2-3 Mb/s a few times.
Any help/ideas appreciated.
Router stats (TG585v8) are:
(Software Release: 8.2.7.8 )
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DSL Connection
Link Information

Uptime: 0 days, 0:40:13
DSL Type: G.992.1 annex A
Channel mode: Interleave
Maximum Bandwidth (Up/Down) [kbps/kbps]: 916 / 7,808
Bandwidth (Up/Down) [kbps/kbps]: 448 / 7,616
Data Transferred (Sent/Received) [kB/MB]: 0.00 / 45.73
Output Power (Up/Down) [dBm]: 11.5 / 17.5
Line Attenuation (Up/Down) [dB]: 7.0 / 14.5
SN Margin (Up/Down) [dB]: 22.0 / 7.0
Vendor ID (Local/Remote): TMMB / ALCB
Loss of Framing (Local/Remote): 0 / 0
Loss of Signal (Local/Remote): 0 / 0
Loss of Power (Local/Remote): 0 / 0
Loss of Link (Remote): 0
Error Seconds (Local/Remote): 0 / 0
FEC Errors (Up/Down): 0 / 11,000
CRC Errors (Up/Down): 5 / 1
HEC Errors (Up/Down): 0 / 0
--------------------------------------------
Speedtest results (over wireless, but not much difference when using a cable):
Current:
Pre-reset:
Worst one in the past few days:

[#2]

Hi there,
Really sorry to hear that. I think the best thing to do would be to record the slow speeds via BT speed test if you can (http://www.speedtester.bt.com) - once we have results from that that show you're below the fault threshold rate then we can get a fault raised for you.

[#3]

Thanks Matt.  Doesn't that just do download speeds though?  I often have download speeds that are as good as I've ever had at this property (from Tiscali/TalkTalk, BT and Plusnet) coupled with what appear to be awful upload speeds (~120 Kb/s).  Of course, that said, I seem to be getting low download speeds as well tonight (2.5 - 3.5 Mb/s).
With the BT speedchecker I know I should, but do I need to connect via cable to the router?  Because that's potentially a problem as the router is in another room.  The signal strength is 4/5 bars and whenever I've used Speedtest.net there seems to be little difference between cabled and wireless.
BTW, what would people expect the range of reasonable upload speeds to be on a line that's usually 5-6 Mb/s download?

[#4]

Quote from: Bromley86

BTW, what would people expect the range of reasonable upload speeds to be on a line that's usually 5-6 Mb/s download?

Upload speed doesn't really vary with line length, on ADSL1 you should always get the 448K sync (unless you pay extra for Max Premium), so you should get around 380Kbit throughput.