Intermittent WAN disconnects.

[#1]

I wonder if anyone can help me diagnose an issue which I've been plagued with since November last year.  I'm having a problem with WAN disconnects. It started off being once or twice a day, with the router logs showing; WAN Connection: WAN(0) link down. This would rectify itself within a minute, but gradually came to a height in December where it would disconnect several times an hour, resulting in contacting Plusnet who said there was a line fault present and sent an Engineer.  Engineer visited Jan 4th and couldn't find any faults, but could clearly see the history of disconnects on his system. Strangely, the frequency of disconnects reduced after his visit, down to a couple of times a day, then subsidising altogether by the beginning of February. Short lived respite though, as they are back and seem to happen roughly at the same time periods every day: 04:30 and 20:30.  Speeds seem to be all over the place since the start of this problem. I usually get around 70Mbps, but since the problems stared I'm lucky to see 45Mbps.  

Quiet Line test: pass.  Silent.

Master socket is the Filtered type.

Modem router: DSL-AX82U  Attached to directly to master socket or extension, makes no difference to the disconnects.

SNR Margin	9.6 dB
Line Attenuation	15.8 dB

Snippet of logs:

Feb 16 20:28:24 WAN Connection: WAN(0) link down.
Feb 16 20:28:26 kernel: [3646645.658707] Line 0: xDSL link down
Feb 16 20:28:26 kernel: [3646645.662335] bcmxtmcfg:ulPhysPort[0] m_ulTrafficMonitorPort[0]
Feb 16 20:28:26 kernel: [3646645.668725] bcmxtmcfg: XTM LinkInfo. P-0, S-DOWN(2), Service =PTM(2)
Feb 16 20:28:26 kernel: [3646645.675402] bcmxtmrt: netif_carrier_off
Feb 16 20:28:26 kernel: [3646645.679523] iudma txq 0 disable
Feb 16 20:28:26 kernel: [3646645.682852] tx_disable context 0x1 from (0x1)
Feb 16 20:28:26 kernel: [3646645.683036] XTM W1B 1542061145
Feb 16 20:28:26 kernel: [3646645.690071] XTM W1E 1542061152
Feb 16 20:28:26 kernel: [3646645.690119] bcmxtmcfg: Connection DOWN, LinkActiveStatus=0x0
Feb 16 20:28:26 kernel: [3646645.690125] bcmxtmcfg: ChkSILI Port = 0, BondingPort = 4
Feb 16 20:28:26 kernel: [3646645.690127] bcmxtmcfg: DSL link mode is 4
Feb 16 20:28:26 kernel: [3646645.690129] DSL LinkMode 4
Feb 16 20:28:26 kernel: [3646645.690136] bcmxtmcfg: ReconfSAR P-0, T-0
Feb 16 20:28:26 kernel: [3646645.690168] bcmxtmcfg: ATM Bonding configured in system. Fallback mode = Enabled
Feb 16 20:28:26 kernel: [3646645.690170] bcmxtmcfg: Bonding State is DATA_IDLE
Feb 16 20:28:26 kernel: [3646645.690173] bcmxtmcfg: SID MODE SET to 12 BIT MODE
Feb 16 20:28:26 kernel: [3646645.690178] bcmxtmcfg: ATM Bonding Mgmt Log Area = d61365bc
Feb 16 20:28:26 kernel: [3646645.690184] BcmXdslDiscardWanDev: lineId=0,bDevDown=0
Feb 16 20:28:26 kernel: [3646645.693842] XTM RXQ[0]: Depth 512, Level 0, Writes 551223863, Reads 551223863, Discards 923, Writes+Discards 551224786
Feb 16 20:28:26 kernel: [3646645.705342] XTM RXQ[1]: Depth 512, Level 0, Writes 87, Reads 87, Discards 0, Writes+Discards 87
Feb 16 20:28:26 DSL: Link up -> down
Feb 16 20:28:26 kernel: [3646645.716674] XTM TXQ[0]: Depth 512, Level 0, Writes 254339522, Reads 254339522, Discards 0, Writes+Discards 254339522
Feb 16 20:28:26 kernel: [3646645.729309] XTM RCQ[0]: Depth 512, Level 0, Writes 254339522, Reads 254339522, Discards 0, Writes+Discards 254339522
Feb 16 20:28:26 kernel: [3646645.740197] Archer XTM rx notify 0x1 (pending 0)
Feb 16 20:28:26 kernel: [3646645.756300] xtm queue 0 forcely claim the untransmitted (0) buffers tx = 489
Feb 16 20:28:27 WAN Connection: Fail to connect with some issues.
Feb 16 20:28:29 kernel: [3646648.579130] Line 0: xDSL G.994 training
Feb 16 20:28:32 WAN Connection: WAN(0) link down.
Feb 16 20:28:38 kernel: [3646657.583132] Line 0: VDSL G.993 started
Feb 16 20:28:43 kernel: [3646662.790074] 3C:E0:72:DC:E8:0A not mesh client, can't update it's ip
Feb 16 20:28:43 kernel: [3646662.790074]
Feb 16 20:28:50 kernel: [3646669.586129] Line 0: VDSL G.993 channel analysis
Feb 16 20:28:51 kernel: [3646671.038533] Line 0: VDSL2 link up, Bearer 0, us=20000, ds=48849
Feb 16 20:28:51 kernel: [3646671.044651] Line 0: VDSL2 link up, Bearer 1, us=0, ds=0
Feb 16 20:28:51 kernel: [3646671.050231] bcmxtmcfg: ULS Port 0
Feb 16 20:28:51 kernel: [3646671.053871] bcmxtmcfg: XTM Link Mode is VDSL G.inpRtx
Feb 16 20:28:51 kernel: [3646671.059233] bcmxtmcfg:ulPhysPort[0] m_ulTrafficMonitorPort[4]
Feb 16 20:28:51 kernel: [3646671.065297] bcmxtmcfg: XTM LinkInfo. P-0, S-UP(1), Service =PTM(2)
Feb 16 20:28:51 kernel: [3646671.071770] bcmxtmcfg: ReconfSAR P-0, T-2
Feb 16 20:28:51 kernel: [3646671.076178] bcmxtmcfg: Reserve TxQueueIdx=0 for vcid 0
Feb 16 20:28:52 kernel: [3646671.081503] ===>ConfigurePtmQueueShaper: ShaperIdx=0 MinRate=0 ShapeRate=0 Mbs=0 MinRateMbs=0, SitUt=600 SitLoUT=19200pulGts[00000000] NON-CO4 DSLAM based operations for PTM CRC & ENET FCS.
Feb 16 20:28:52 kernel: [3646671.098930] SetTxQueue for InfoSize 0 QueueIndex 0
Feb 16 20:28:52 kernel: [3646671.104029] TXDMA drop alg 0 Lo minThresh 0 maxThresh 0 hi minThresh 0 maxThresh 0
Feb 16 20:28:52 kernel: [3646671.111784] iudma txq 0 enable devId[0] txVcid[0] base_buff_status[000000f3]
Feb 16 20:28:52 kernel: [3646671.119024] bcmxtmrt: netif_carrier_on
Feb 16 20:28:52 kernel: [3646671.123137] bcmxtmcfg: Connection UP, LinkActiveStatus=0x1, US=20000000, DS=48849000
Feb 16 20:28:52 kernel: [3646671.131229] bcmxtmcfg: ChkSILI Port = 0, BondingPort = 4
Feb 16 20:28:52 kernel: [3646671.137188] bcmxtmcfg: DSL link mode is 4
Feb 16 20:28:52 kernel: [3646671.141593] DSL LinkMode 4
Feb 16 20:28:56 DSL: Link down -> up
Feb 16 20:28:57 WAN Connection: WAN was restored.

Moderator's note by Mike (Mav): Post released from Spam Filter.

[#2]

Insane amount of disconnects last night. Rough count its around 17, skimming over the logs. That's the worst I've seen to date.

Snippets from logs. Hopefully someone can help. 

Feb 18 03:35:02 DSL: Link up -> down

Feb 18 03:35:03 kernel: [31511.727144] Line 0: xDSL G.994 training

Feb 18 03:35:11 WAN Connection: WAN(0) link down.

Feb 18 03:35:27 DSL: Link down -> up

Feb 18 03:37:17 DSL: Link up -> down

Feb 18 03:37:22 WAN Connection: WAN(0) link down.

Feb 18 03:37:42 DSL: Link down -> up

Feb 18 03:37:42 WAN Connection: WAN was restored.

Feb 18 06:44:40 WAN Connection: WAN(0) link down.

Feb 18 06:45:12 kernel: [42920.758264] Line 0: xDSL link down

Feb 18 06:45:17 DSL: Link up -> down

Feb 18 06:45:20 WAN Connection: Fail to connect with some issues.

Feb 18 06:45:25 kernel: [42933.193136] Line 0: VDSL G.993 started

Feb 18 06:45:25 WAN Connection: WAN(0) link down.

Feb 18 06:45:31 pppd[2111]: Serial link appears to be disconnected.

Feb 18 06:45:36 kernel: [42944.196137] Line 0: VDSL G.993 channel analysis

Feb 18 06:45:37 pppd[2111]: Connection terminated.

Feb 18 06:45:37 pppd[2111]: Modem hangup

Feb 18 06:45:42 DSL: Link down -> up

Feb 18 06:47:12 DSL: Link up -> down

Feb 18 06:47:16 WAN Connection: Fail to connect with some issues.

Feb 18 06:47:21 WAN Connection: WAN(0) link down.

Feb 18 06:47:21 kernel: [43049.228143] Line 0: VDSL G.993 started

Feb 18 06:47:33 kernel: [43061.231137] Line 0: VDSL G.993 channel analysis

Feb 18 06:47:33 kernel: [43061.715669] Line 0: VDSL2 link up, Bearer 0, us=18669, ds=33609

Feb 18 06:47:33 kernel: [43061.721614] Line 0: VDSL2 link up, Bearer 1, us=0, ds=0

Feb 18 06:47:37 DSL: Link down -> up

Feb 18 06:47:41 WAN Connection: WAN was restored.

Feb 18 06:48:37 DSL: Link up -> down

Feb 18 06:48:37 WAN Connection: WAN(0) link down.

Feb 18 06:48:39 pppd[2111]: Serial link appears to be disconnected.

Feb 18 06:48:41 WAN Connection: Fail to connect with some issues.

Feb 18 06:48:45 pppd[2111]: Connection terminated.

Feb 18 06:48:45 pppd[2111]: Modem hangup

Feb 18 06:48:45 kernel: [43133.260158] Line 0: VDSL G.993 started

Feb 18 06:48:46 WAN Connection: WAN(0) link down.

Feb 18 06:48:57 kernel: [43145.267145] Line 0: VDSL G.993 channel analysis

Feb 18 06:48:58 kernel: [43146.011171] Line 0: VDSL2 link up, Bearer 0, us=20000, ds=64344

Feb 18 06:48:58 kernel: [43146.017111] Line 0: VDSL2 link up, Bearer 1, us=0, ds=0

Feb 18 06:49:02 DSL: Link down -> up

Feb 18 06:49:28 kernel: [43176.010985] Line 0: xDSL link down

Feb 18 06:49:30 pppd[2111]: Timeout waiting for PADO packets

Feb 18 06:49:31 kernel: [43179.273144] Line 0: xDSL G.994 training

Feb 18 06:49:32 DSL: Link up -> down

Feb 18 06:49:36 WAN Connection: Fail to connect with some issues.

Feb 18 06:49:40 kernel: [43188.276143] Line 0: VDSL G.993 started

Feb 18 06:49:41 WAN Connection: WAN(0) link down.

Feb 18 06:49:57 DSL: Link down -> up

Feb 18 06:50:42 DSL: Link up -> down

Feb 18 06:50:44 kernel: [43252.309141] Line 0: xDSL G.994 training

Feb 18 06:50:45 pppd[2111]: Timeout waiting for PADO packets

Feb 18 06:50:46 WAN Connection: Fail to connect with some issues.

Feb 18 06:50:51 WAN Connection: WAN(0) link down.

Feb 18 06:50:53 kernel: [43261.313158] Line 0: VDSL G.993 started

Feb 18 06:51:05 kernel: [43273.316137] Line 0: VDSL G.993 channel analysis

Feb 18 06:51:06 kernel: [43274.446152] Line 0: VDSL2 link up, Bearer 0, us=20000, ds=66999

Feb 18 06:51:06 kernel: [43274.452093] Line 0: VDSL2 link up, Bearer 1, us=0, ds=0

Feb 18 06:51:07 DSL: Link down -> up

Feb 18 06:51:52 DSL: Link up -> down

Feb 18 06:51:53 kernel: [43321.333138] Line 0: xDSL G.994 training

Feb 18 06:51:55 WAN Connection: Fail to connect with some issues.

Feb 18 06:52:00 pppd[2111]: Timeout waiting for PADO packets

Feb 18 06:52:00 WAN Connection: WAN(0) link down.

Feb 18 06:52:17 DSL: Link down -> up

Feb 18 06:52:47 DSL: Link up -> down

Feb 18 06:52:50 WAN Connection: Fail to connect with some issues.

Feb 18 06:52:55 WAN Connection: WAN(0) link down.

Feb 18 06:52:56 kernel: [43384.351138] Line 0: VDSL G.993 started

Feb 18 06:53:07 kernel: [43395.354148] Line 0: VDSL G.993 channel analysis

Feb 18 06:53:08 kernel: [43396.905929] Line 0: VDSL2 link up, Bearer 0, us=20000, ds=66999

Feb 18 06:53:08 kernel: [43396.911882] Line 0: VDSL2 link up, Bearer 1, us=0, ds=0

Feb 18 06:53:12 DSL: Link down -> up

Feb 18 06:53:52 DSL: Link up -> down

Feb 18 06:53:52 kernel: [43440.362143] Line 0: xDSL G.994 training

Feb 18 06:53:55 WAN Connection: Fail to connect with some issues.

Feb 18 06:54:00 WAN Connection: WAN(0) link down.

Feb 18 06:54:01 kernel: [43449.365140] Line 0: VDSL G.993 started

Feb 18 06:54:12 kernel: [43460.369144] Line 0: VDSL G.993 channel analysis

Feb 18 06:54:13 kernel: [43461.798026] Line 0: VDSL2 link up, Bearer 0, us=13289, ds=34789

Feb 18 06:54:13 kernel: [43461.803977] Line 0: VDSL2 link up, Bearer 1, us=0, ds=0

Feb 18 06:54:17 DSL: Link down -> up

Feb 18 06:54:42 DSL: Link up -> down

Feb 18 06:54:44 kernel: [43492.376153] Line 0: xDSL G.994 training

Feb 18 06:54:46 WAN Connection: Fail to connect with some issues.

Feb 18 06:54:51 WAN Connection: WAN(0) link down.

Feb 18 06:55:07 DSL: Link down -> up

Feb 18 07:10:57 WAN Connection: WAN(0) link down.

Feb 18 07:11:01 WAN Connection: WAN was restored.

Feb 18 07:42:05 WAN Connection: WAN(0) link down.

Feb 18 07:42:06 kernel: [46334.108555] Line 0: xDSL link downFeb 18 07:42:07 DSL: Link up -> down

Feb 18 07:42:09 kernel: [46337.581142] Line 0: xDSL G.994 training

Feb 18 07:42:10 WAN Connection: Fail to connect with some issues.

Feb 18 07:42:15 WAN Connection: WAN(0) link down.

Feb 18 07:42:32 DSL: Link down -> up

Feb 18 07:42:35 WAN Connection: WAN was restored.

Feb 18 07:43:02 WAN Connection: WAN(0) link down.

Feb 18 07:43:06 pppd[2111]: Serial link appears to be disconnected.

Feb 18 07:43:12 DSL: Link up -> down

Feb 18 07:43:37 DSL: Link down -> up

Feb 18 07:47:03 WAN Connection: WAN(0) link down.

Feb 18 07:47:17 DSL: Link up -> down

Feb 18 07:47:18 kernel: [46646.652141] Line 0: xDSL G.994 training

Feb 18 07:47:22 WAN Connection: Fail to connect with some issues.

Feb 18 07:47:27 WAN Connection: WAN(0) link down.

Feb 18 07:47:42 DSL: Link down -> up

Feb 18 07:47:47 WAN Connection: WAN was restored.

Feb 18 07:48:44 WAN Connection: WAN(0) link down.

Feb 18 07:48:47 kernel: [46735.560503] Line 0: xDSL link down

Feb 18 07:48:52 DSL: Link up -> down

Feb 18 07:48:54 WAN Connection: Fail to connect with some issues.

Feb 18 07:48:59 WAN Connection: WAN(0) link down.

Feb 18 07:48:59 kernel: [46747.684157] Line 0: VDSL G.993 started

Feb 18 07:49:11 kernel: [46759.687142] Line 0: VDSL G.993 channel analysis

Feb 18 07:49:13 kernel: [46760.887622] Line 0: VDSL2 link up, Bearer 0, us=19746, ds=49446

Feb 18 07:49:13 kernel: [46760.893575] Line 0: VDSL2 link up, Bearer 1, us=0, ds=0

Feb 18 07:49:17 DSL: Link down -> up

Feb 18 07:49:19 WAN Connection: WAN was restored.

Feb 18 07:49:57 kernel: [46804.887349] Line 0: xDSL link down

Feb 18 07:49:57 DSL: Link up -> down

Feb 18 07:49:59 WAN Connection: Fail to connect with some issues.

Feb 18 07:49:59 kernel: [46807.705641] Line 0: xDSL G.994 training

Feb 18 07:50:04 WAN Connection: WAN(0) link down.

Feb 18 07:50:22 DSL: Link down -> up

Feb 18 07:50:24 WAN Connection: WAN was restored.

Feb 18 07:51:05 WAN Connection: WAN(0) link down.

Feb 18 07:51:09 pppd[2111]: Serial link appears to be disconnected.

Feb 18 07:51:09 pppd[2111]: Connection terminated.

Feb 18 07:51:10 WAN Connection: Fail to connect with some issues.

Feb 18 07:51:19 pppd[2111]: Connected to 14:7b:ac:b4:11:77 via interface wan0

Feb 18 07:51:19 pppd[2111]: Connect: ppp0 <--> wan0

Feb 18 07:51:19 pppd[2111]: CHAP authentication succeeded

Feb 18 07:51:20 WAN Connection: WAN was restored.

[#3]

@Thatwilllldo12 

I suggest you report a fault using the automated system

https://www.plus.net/help/report-a-problem/broadband/ 

HTH

[#4]

Thanks @Dan_the_Van. I'll ring them again and see.  I've already done this dance with reporting the issue, last engineer visit was less than 6 weeks ago could not find a problem after several hours of testing.  I know this can't go on like this. My connection was always rock solid; It's only been doing this since November.

[#5]

Have you checked the landline phone for noise, it could be noise causing the issue, dial 17070 option 2, the line should be silent.

If you have a Master Socket 5c it is worth checking the faceplate is fully seated and if possible connect the modem to the test socket behind the face plate for a while to see of that the cause

HTH

[#6]

Quite line test is silent and have already had the router plugged into the Master socket ( and test port) which made no difference to the dropouts.  Bit of a head scratcher.

[#7]

The evidence suggests a line issue which needs investigating further, you should not have than many failures. 

[#8]

@Dan_the_Van  That's what I'm leaning towards. That or the Modem-Router is taking a bath; but then it's less than 6 months old and the logs suggest a line drop?

Update:  Just got of the blower and technical have said there's still a fault showing on the line, despite the engineer not being able to find anything on their last visit. So another engineer has been booked.  Fingers crossed. I'll post an update after the visit.

[#9]

Another 12 disconnects during the night. Has been stable since 7:45am. Something I failed to mention in my original post is that since this problem started, speeds fluctuate a lot. I used to see around 70+Mbs, but it's been oscillating between 45 to 60Mbps 

Feb 18 21:06:38 DSL: Link up -> down

Feb 18 21:06:43 WAN Connection: WAN(0) link down.

Feb 18 21:07:03 DSL: Link down -> up

Feb 18 21:07:08 WAN Connection: WAN was restored.

Feb 18 21:07:35 WAN Connection: WAN(0) link down.

Feb 18 21:08:00 WAN Connection: WAN was restored

Feb 19 03:49:43 DSL: Link up -> down

Feb 19 03:49:54 WAN Connection: WAN(0) link down.

Feb 19 03:50:08 DSL: Link down -> up

Feb 19 03:50:08 WAN Connection: WAN was restored.

Feb 19 07:22:28 WAN Connection: WAN(0) link down.

Feb 19 07:22:33 WAN Connection: WAN was restored.

Feb 19 07:23:15 WAN Connection: WAN(0) link down.

Feb 19 07:23:18 DSL: Link up -> down

Feb 19 07:23:43 DSL: Link down -> up

Feb 19 07:24:08 DSL: Link up -> down

Feb 19 07:24:33 DSL: Link down -> up

Feb 19 07:24:35 WAN Connection: WAN was restored.

Feb 19 07:27:18 WAN Connection: WAN(0) link down.

Feb 19 07:27:21 Line 0: xDSL link down

Feb 19 07:27:48 DSL: Link down -> up

Feb 19 07:27:52 WAN Connection: WAN was restored.

Feb 19 07:29:03 WAN Connection: WAN(0) link down.

Feb 19 07:29:05 kernel: [131952.108100] Line 0: xDSL link down

Feb 19 07:29:08 DSL: Link up -> down

Feb 19 07:29:08 WAN Connection: Fail to connect with some issues.

Feb 19 07:29:13 WAN Connection: WAN(0) link down.

Feb 19 07:29:33 DSL: Link down -> up

Feb 19 07:29:38 WAN Connection: WAN was restored.

eb 19 07:32:49 kernel: [132176.420749] Line 0: xDSL link down

Feb 19 07:32:51 WAN Connection: WAN(0) link down.

Feb 19 07:32:52 kernel: [132179.732144] Line 0: xDSL G.994 training

Feb 19 07:32:53 DSL: Link up -> downeb 19 07:33:18 DSL: Link down -> up

Feb 19 07:33:20 WAN Connection: WAN was restored.

Feb 19 07:34:03 WAN Connection: WAN(0) link down.

Feb 19 07:34:06 Line 0: xDSL link down

Feb 19 07:34:08 DSL: Link up -> down

Feb 19 07:34:10 Line 0: xDSL G.994 training

Feb 19 07:34:12 WAN Connection: Fail to connect with some issues.

Feb 19 07:34:17 WAN Connection: WAN(0) link down.

Feb 19 07:34:33 DSL: Link down -> up

Feb 19 07:34:37 WAN Connection: WAN was restored.

Feb 19 07:36:19 WAN Connection: WAN(0) link down.

Feb 19 07:36:24 WAN Connection: WAN was restored.

Feb 19 07:45:50 WAN Connection: WAN(0) link down.

Feb 19 07:45:53 kernel: [132959.900139] Line 0: xDSL G.994 training

Feb 19 07:45:53 DSL: Link up -> down

Feb 19 07:45:53 kernel: [132959.900139] Line 0: xDSL G.994 training

Feb 19 07:45:53 DSL: Link up -> down

[#10]

Well, as I feared would happen, the visiting Engineer found nothing after two hours of fault finding. I did raise this as a one of my concerns to Plusnet seeing an Engineer was here six weeks ago, but they said they had requested a higher level Engineer to visit. So here we are. Line test came up clean and RT test showed normal. Interestingly one of the tests to the exchange threw up 11000 connection faults? The most he's seen, apparently. I have no idea what this means. But he couldn't get it to repeat.

So to roll back. The first Engineer in January noted there was a bridge tap on the line ( a data extension to another room fitted by BT a long while ago) but tested this to be fine and made a note of it as it does show up when tested by plusnet/openreach. However, to preempt this being an issue I moved the router to the master socket when the problems started, where it has remained since.  Todays visiting Engineer seems to think the bridge tap/extension could still be an issue, even though the router is not connected to it, so has eliminated this by disconnecting it and has jerry rigged the connection behind the faceplate so everything runs through a filter dongle, eliminating the filtered faceplate, to test it for a week and see if the issue persists. His thinking is that the exchange equipment is sensitive to bridge taps and cuts them off.  So now none of my PC's are hardwired to the internet anymore, which is little frustrating as none of them are wifi enabled, so I have to run long Cat 5 cables to my hallway to get them online. But if it helps find the issue then I don't mind the house looking like I'm stealing electric from the neighbours.

The saga continues.....

[#11]

If your router is plugged into the 'filter dongle' it is running exactly the same way as it was when connected to the filtered faceplate - I assume the engineer has plugged it into the test socket?

[#12]

@jab1  Correct.  For the life of me I can't see how this is going to resolve the issue. But I'll play along. 

[#13]

It will 'resolve' it, in that when plugged into the test socket, all other extensions are effectively dead, but a more elegant, and the proper way, is to get rid of the bridge tap.

[#14]

@Thatwilllldo12 

The fact that you now need to run a CAT 5 cable to the hallway suggests to me that you previously had the hub hung on to an extension lead between your master socket and hall, with extension leads being fed off the master socket. This would introduce the reported bridge tap with potential performance problems. Regardless of whether this lash up fixes your fault, if I am correct then I would recommend that a filtered faceplate is fitted at the master socket location, site the hub close to this and permanently install a CAT 5e (not CAT 5) cable to the hall. If you need multple Ethernet outlets in the Hall then an Ethernet switch is inexpensive.

[#15]

Todays visiting Engineer seems to think the bridge tap/extension could still be an issue, even though the router is not connected to it, so has eliminated this by disconnecting it and has jerry rigged the connection behind the faceplate so everything runs through a filter dongle, eliminating the filtered faceplate

The extension cable needs to be disconnected to remove a bridge tap, not using the extension will not eliminate the bridge tap or any interference being caused.

It should not be necessary to jerry rig the wiring to allow a ADSL dongle filter to work in a master socket, it just plugs into the test behind the faceplate.

Which version of master socket do you have, is this where the copper telephone line comes into your property?

It should be noted the ADSL filter is to filter out the DSL signal from the phone and it circuit is bypassed for DSL signals connection to the modem. It provides the required RJ11 connection for the modems DSL cable plug.