This topic

A tale of two houses....

BarkingMadBarking — Mon, 15 Aug 2022 16:07:12 GMT

My neighbour and I are connected through the same pole, to the same cabinet. We're both on Fibre1. My neighbour uses a BT H3 and I use a non BT modem/router - although I do have a BT SH2.

I have a good connection - max observed speed 54.57/9.5

My neighbour doesn't 34.99/1.17 - although when I looked a few days ago, the max observed speeds were 24.99/6.65

My neighbours line is quiet (performed a quiet line test); there is nothing apart from a wireless base station and HH3 connected to the master socket - no other internal wiring. We have discussed the speed with the BT fault team and we've been told everything is fine. A non Openreach engineer will visit in a couple of weeks to look at the inside of the house - but I don't think this will resolve the issue.

The HH3 logs show many resyncs and HH3 restarts. My theory, is for some reason there is an "issue" - hence the resyncs, and after the HH3 sees so many resyncs within a certain time frame, it reboots itself. All these “loss of connection” events have made DLM place a cap on the line - and hence the lower speeds. The observed speeds ending in ".99" possibly support my theory.

Would my thoughts be reasonable and do you have any suggestions to correct the issue?

Perhaps the HH3 is faulty; perhaps there is some interference within the property causing the "issue"; other?

I also note that the neighbour on the other side of my neighbour has problems where the line repeatedly drops. BT have visited many times and have replaced an underground twisted pair cable, as well as all other cables but the problem still persists. Linked?

Thoughts please

Re: A tale of two houses....

licquorice — Mon, 15 Aug 2022 16:15:04 GMT

Its possible its a faulty hub, its also possible that there is a faulty cable. Only an Openreach engineer can diagnose. You could try lending your neighbour your SH2 to see if that improves things.

Re: A tale of two houses....

BarkingMadBarking — Mon, 15 Aug 2022 18:10:48 GMT

@licquorice

Thanks. I've given my neighbour my SH2 and set it to only use 2.4 (by disabling 5) with same SSID/password as her HH5. All my neighbour's devices connected using the 2.4 wifi.

My neighbour has the HH5 - not HH3 as stated in my original post.

I cannot see my SH2 increasing the speed if it DLM capped - it probably needs a DLM reset. It may give more details regarding the re-starts / re-syncs.

Any suggestions on how we obtain a visit from an Openreach engineer. BT fault team says there is nothing wrong with the line and therefore the system says an Openreach engineer is not required.

Re: A tale of two houses....

licquorice — Mon, 15 Aug 2022 18:18:56 GMT

Its going to be difficult as their speed is just above the handback threshold. If the SH2 is stable, proving the fault to be with the hub rather than line, DLM should relent after a few weeks and restore speed. If the line is still unstable with the SH2, you can only keep pestering the helpdesk to send an engineer unfortunately.

Re: A tale of two houses....

BarkingMadBarking — Fri, 19 Aug 2022 07:54:13 GMT

@licquorice

The SH2 is providing better results: sync 34.999/6.743 and it is not rebooting. The max speed according to the SH2 is around 40/6.7. It's still early days.

If there is a cap on the line, which I think there is given that sync speed (34.999) then I understand DLM will not remove the cap - only a reset will remove the cap. Am I mistaken?

Re: A tale of two houses....

imjolly — Fri, 19 Aug 2022 08:10:37 GMT

@BarkingMadBarking wrote:

@licquorice

If there is a cap on the line, which I think there is given that sync speed (34.999) then I understand DLM will not remove the cap - only a reset will remove the cap. Am I mistaken?

yes if line remains stable then DLM should start to reduce noise margin and increase speed until up to max line capable.

as DLM does not affect the attainable speed what is speed shown on SH2

Re: A tale of two houses....

BarkingMadBarking — Fri, 19 Aug 2022 08:34:14 GMT

@imjolly

Here are the latest stats...straight from the export...and it did export "Fireware version"

Product name,BT Smart Hub 2
Serial number,+091301+2015009920
Fireware version,v0.35.01.06093-BT (Thu Jun 9 11:13:37 2022)
Board version,R01
GUI version,1.74 12_11_2020
DSL uptime,2 days 4 Hours 21 Mins 23 Secs
Data rate,6.7 Mbps / 35.0 Mbps
Maximum Data rate,6.8 Mbps / 40.4 Mbps
Noise margin,6.0/8.5
Line attenuation,10.6/22.1
Signal attenuation,10.6/22.5

The f/w was updated two days ago.

For comparison, my non BT router with a user limited download sync of 40000 shows:

adsl info --stats
adsl: ADSL driver and PHY status
Status: Showtime
Last Retrain Reason: 1
Last initialization procedure status: 0
Max: Upstream rate = 9401 Kbps, Downstream rate = 46669 Kbps
Bearer: 0, Upstream rate = 9401 Kbps, Downstream rate = 40000 Kbps
Bearer: 1, Upstream rate = 0 Kbps, Downstream rate = 0 Kbps
Link Power State: L0
Mode: VDSL2 Annex B
VDSL2 Profile: Profile 17a
TPS-TC: PTM Mode(0x0)
Trellis: U:ON /D:ON
Line Status: No Defect
Training Status: Showtime
Down Up
SNR (dB): 5.1 6.3
Attn(dB): 22.1 0.0
Pwr(dBm): 11.6 7.0