Continuous Disconnections "Appear" To Have Stopped...

Question

BACKGROUND (cutting a VERY long story "long")  [skip to the next section if you're bored to tears]:
- With BT Broadband since early February. Had continuous disconnections since joining, which added to the dreaded DLM from BT resulted in ever-slow speeds (at some popint we wre under 0.1 Mbps)
- Previously with Virgin Media BroadBand + BT line rental. We never had any issues of disconnections or slow speeds. Couldn't fault VM (except that they got riff of their BB customers to focus on Fibre services not available in our area).
- The first-tier of Customer Services are all very polite people but, frankly, have been of no help at all. Countless line checks were made, mostly "concluding that the line was OK and the connection stable". Well, one only had to check the Event Logs, which would soon be out of memory within a day, showing disconnection after disconnection.
- The second-tier could not help also and finally decided an engineer had to call at the property.
- The engineeer failed to show up.
- The engineer visit was rescheduled, the engineer did show up. He confirmed our internal installation is OK, put the onus on some
work needed "down a manhole in a road nearby" and that a different team had to take over.
- As far as I am aware, this work had been seen to (although I initially had my doubts: BT phone services told me "everything (was) sorted now" whilst I was tearing out my hair with the same problems and speeds under 0.1 Mbps
- I *think* that my profile was reset once or twice by now, our speeds would get about 6 Mbps, rapidly dropping after
disconnections.
- I have noticed BB disconnections when using the internet on my Pc but ALSO when the PC was off and there was no wired or wireless use whatsoever.  
- BT KEEPS CLOSING UP THE FAULTS I OPEN & RE-OPEN (HOW VERY CONVENIENT!) OUR FAULT HAS BEEN PRESENT FOR NEAR 3 MONTHS NOW, IS THAT TOO EMBARRASSING TO DISPLAY IN bt.com/fault?
- Online complaint filed... Ignored by BT.
- 3-page letter of complaint sent to BT... Got an awfully generic reply: "Hopefully you know by now what BT is doing to sort this problem" I DO ACTUALLY KNOW... THEY ARE DOING ABSOLUTELY NOTHING!  BT gave an email address to reply: I replied 7 days ago asking what's going on, now have re-sent the e-mail (2 days ago): Nothing. MAYBE THE SUPPLIED OMBUDSMAN CONTACT WILL NEED TO BE USED NEXT?
- I keep being promised refunds of line rental, etc. These are yet to materialize as "I will get this when the fault is solved". This of course works on the assumption that my fault will EVER be solved. ALL I REALLY WANT IS: SORT THIS NEVERENDING FAULT.
- Oh, and BT Direct Debit was increased to more than advised (yes, our experience was dreadful so far in ALL aspects) - We are dealing with this separately, DD has now been now reduced... I'm looking forward to the next quarterly bill to confirm I'm not being overcharged (I've honestly lost all trust in all things BT).
- I am an engineer myself and the kindest assessment of the situation would be that BT Customer Services are applying ZERO LOGIC in trying to sort this problem.
CURRENT SITUATION:
- BT Customer Services appear to be avoiding us. They did not call us back to follow up the case and frankly, I am very busy these days and have little time to engage in another gruelling wait + futile conversation (typically near an hour in total) to get absolutely nowhere.
- Stable connection for almost 7 days now.
- Speed capped at 2 Mbps, actual speed is 1.4 to 1.5 Mbps (and has been so for at least 4-5 days).
Onto the technical stuff........
OUR CONNECTION:
- Wired (ethernet) to desktop PC.
- Hub4 Connected to test socket of NTE5, using supplied filter.
- Only one phone connected, via the same filter at the main (test) socket.
- At different times during troubleshooting (weeks ago), I took to, one by one, changing the filter, the ethernet cable and the phone cable supplied by BT. I also changed to different ethernet ports of the Hub, no joy... None of this made any difference so all original cables and filter are again in place.
- The engineer neglected to check the HUb, convinced it was a line problem. Over a month ago, I temporarily replaced the Hub with an old Netgear supplied by Virgin. At that time this made no difference but then the disconnection rate was appalling and wonder if there was an actual fault in the line now and now this stabilized? Regardless, I've been thinking whether my old Netgear would perform better but I have been patient and trying to build up more days of stable connection... BUT 6 days+ of solid connection and I'm still at 1.4 Mbps????
- There are NO other phones or telephone extensions at the property.
- We occasionally use our mobile phones via wireless. Wireless connection is fine (when main connection is present, of course)
Hub "Helpdesk" Info:
1. Product name:    BT Home Hub
2. Serial number:    +068340+NQ44321122
3. Firmware version:    Software version 4.7.5.1.83.8.130.1.17 (Type A) Last updated Unknown
4. Board version:    BT Hub 4A
5. ADSL uptime:    6 days, 15:01:52
6. Bandwidth:    96 / 1888
7. Data sent/received:    229.6 MB / 3.5 GB
8. Broadband username:    [xxedited_out_xx]@btbroadband.com
9. BT FON:    No
10. 2.4 GHz Wireless network/SSID:    [xxedited_out_xx]
11. 2.4 GHz Wireless connections:    Enabled (802.11 b/g/n (Recommended)) 20 MHz, WPS enabled
12. 2.4 GHz Wireless security:    WPA and WPA2
13. 2.4 GHz Wireless channel:    Automatic / 6
14. 5 GHz Wireless network/SSID:    [xxedited_out_xx]
15. 5 GHz Wireless connections:    Enabled (802.11 n 40 MHz (Recommended)) 20/40 MHz, WPS enabled
16. 5 GHz Wireless security:    WPA2
17. 5 GHz Wireless channel:    Automatic / 40
18. Firewall:    Default
19. MAC Address:    d0:84:b0:e4:51:c6
20. VPI/VCI:    0 / 38
21. Modulation:    G.992.1 Annex A
22. Latency type:    Interleaved
23. Software variant:    -
24. Boot loader:    -
Noise Rates Margin and Line Rates of last "events" at the time of last noted disconnections (Note log dates, no updates since 15 April, when last disconnections occurred):
04:50:49, 15 Apr.    (611767.630000) DSL noise margin: 7.00 dB upstream, 1.20 dB downstream
04:50:49, 15 Apr.    (611767.560000) DSL line rate: 96 Kbps upstream, 1888 Kbps downstream
04:48:38, 15 Apr.    (611636.000000) DSL noise margin: 28.00 dB upstream, 15.10 dB downstream
04:48:38, 15 Apr.    (611635.920000) DSL line rate: 448 Kbps upstream, 7168 Kbps downstream
04:48:04, 15 Apr.    (611602.640000) DSL noise margin: 13.00 dB upstream, 15.20 dB downstream
04:48:04, 15 Apr.    (611602.560000) DSL line rate: 448 Kbps upstream, 1408 Kbps downstream
04:45:30, 15 Apr.    (611448.390000) DSL noise margin: 28.00 dB upstream, 15.20 dB downstream
04:45:30, 15 Apr.    (611448.320000) DSL line rate: 448 Kbps upstream, 7808 Kbps downstream
04:45:06, 15 Apr.    (611423.970000) DSL noise margin: 14.00 dB upstream, 14.80 dB downstream
04:45:06, 15 Apr.    (611423.900000) DSL line rate: 448 Kbps upstream, 1536 Kbps downstream
BT Availability Checker:
Telephone Number [xx_edited_out_xx] on Exchange LYNDHURST is served by Cabinet 6
Featured Products / Downstream Line Rate(Mbps) / Upstream Line Rate(Mbps) / Downstream Range(Mbps) / Availability Date
ADSL Max     Up to 8     --     7 to 8     Available
Fixed Rate     2     --     --     Available
BTWholesale Speed test:
1. Best Effort Test: -provides background information.
Download  Speed: 1.47 Mbps
Max Achievable Speed: 2 Mbps
 Download speedachieved during the test was - 1.47 Mbps
 For your connection, the acceptable range of speeds is 0.4 Mbps-2 Mbps.
 Additional Information:
 Your DSL Connection Rate :1.89 Mbps(DOWN-STREAM), 0.1 Mbps(UP-STREAM)
 IP Profile for your line is - 1.5 Mbps
Questions/Comments:
- I thought it took 3 to 5 days of solid connection for broadband speed to be bumped up? How long should I now wait???
- Does my IP profile need to be reset? (Note: I'm dreading that this will again result in 1-2 days of 6Mbps, followed by disconnections, followed by unusable sepeeds again, as this pattern a few times now).
- Last DSL noise margin stats : "7.00 dB upstream, 1.20 dB downstream"... Any comments on this? Isn't 6 dB considered normal, and the lower this figure the better?
- Can anyone help here before we abandon all hope, stop paying our bill and complain to Trade Standards/Ombudsman/etc??

Answer 1

@ imjolly: Many thanks.
I set the alarm 5 minutes early in order to restart the Hub this morning. Do I believe in coincidences? Sometimes... After 7 days of solid connection, several restarts occurred while my PC was off (Hub's always on) in the early hours of this morning.
As such, I was correct in my cautiousness when naming the thread "Disconnections APPEAR To Have Stopped... " and I am now able to offer new stats without any manual intervention:
06:06:35, 22 Apr.    ( 6977.200000) DSL noise margin: 16.00 dB upstream, 15.00 dB downstream
06:06:35, 22 Apr.    ( 6977.130000) DSL line rate: 448 Kbps upstream, 2272 Kbps downstream
06:03:52, 22 Apr.    ( 6814.210000) DSL noise margin: 15.00 dB upstream, 15.00 dB downstream
06:03:52, 22 Apr.    ( 6814.140000) DSL line rate: 448 Kbps upstream, 2176 Kbps downstream
06:01:57, 22 Apr.    ( 6698.960000) DSL noise margin: 16.00 dB upstream, 14.90 dB downstream
06:01:57, 22 Apr.    ( 6698.890000) DSL line rate: 448 Kbps upstream, 2176 Kbps downstream
06:00:35, 22 Apr.    ( 6616.720000) DSL noise margin: 27.00 dB upstream, 15.10 dB downstream
06:00:35, 22 Apr.    ( 6616.650000) DSL line rate: 448 Kbps upstream, 7808 Kbps downstream
05:53:58, 22 Apr.    ( 6219.650000) DSL noise margin: 15.00 dB upstream, 15.00 dB downstream
05:53:58, 22 Apr.    ( 6219.580000) DSL line rate: 448 Kbps upstream, 2176 Kbps downstream
05:39:17, 22 Apr.    ( 5339.020000) DSL noise margin: 16.00 dB upstream, 15.00 dB downstream
05:39:17, 22 Apr.    ( 5338.950000) DSL line rate: 448 Kbps upstream, 2208 Kbps downstream
05:38:52, 22 Apr.    ( 5314.130000) DSL noise margin: 11.00 dB upstream, 24.80 dB downstream
05:38:52, 22 Apr.    ( 5314.060000) DSL line rate: 448 Kbps upstream, 3072 Kbps downstream
04:11:23, 22 Apr.    ( 64.660000) DSL noise margin: 11.00 dB upstream, 14.90 dB downstream
04:11:23, 22 Apr.    ( 64.500000) DSL line rate: 448 Kbps upstream, 1952 Kbps downstream
Prior to disconnections I note in the main log entries like this one:
04:09:57, 22 Apr.    (1214109.300000) PPP LCP Send Termination Request [User request]
"User request" is not at all MY request... Does this indicate any manual intervention from BT? (I expect not, but I'm only curious). May post full logs if required.
Thanks in advance for any help.