ADSL slows to a halt at night - SNR OK

I PlusNet ADSL and am generally very happy with it, my router is Speedtouch 585 v6. With a line attenuation of nearly 50db I normally connect at between 2 and 4 megabits.

However the last few nights the ADSL has ground to a near halt (dial up speeds) during the evening and night. Restarting the router makes no difference, the next day it is fine again.

What I find strange is the SNR is fine (around 6dB) but the number of CRC and HEC errors shoots up when the connection is bad. What could cause this?

Is there anything I can do to help the connection at night? At the moment it is getting unusable.

Below are the stats for the last day, with this connection it was slow all last night, fine during the day and slow again tonight.

Link Information

Uptime: 1 day, 0:33:24
Modulation: G.992.1 Annex A
Bandwidth (Up/Down) [kbps/kbps]: 448 / 2,560
Data Transferred (Sent/Received) [MB/MB]: 34.09 / 337.33
Output Power (Up/Down) [dBm]: 11.5 / 16.5
Line Attenuation (Up/Down) [dB]: 26.5 / 49.0
SN Margin (Up/Down) [dB]: 19.0 / 7.0
Vendor ID (Local/Remote): TMMB / µ
Loss of Framing (Local/Remote): 0 / 0
Loss of Signal (Local/Remote): 3 / 0
Loss of Power (Local/Remote): 0 / 0
Loss of Link (Remote): 0
Error Seconds (Local/Remote): 53,940 / 0
FEC Errors (Up/Down): 106 / 0
CRC Errors (Up/Down): 108 / 2,548,697
HEC Errors (Up/Down): 172 / 2,379,775


Any ideas?

Are those stats during a problem period?

Uptime: 1 day, 0:33:24

Error Seconds (Local/Remote): 53,940 / 0


FEC Errors (Up/Down): 106 / 0
CRC Errors (Up/Down): 108 / 2,548,697
HEC Errors (Up/Down): 172 / 2,379,775

Most of the data that you are actually getting has taken several attempts to arrive.

It seems likely that something has gone wrong with your internal wiring - damaged extension or filter or possibly something in your house or nearby has started generating a lot of interference and you still have the ringwire attached or are running the router on a plug in extension.

Have a read of http://www.dslzoneuk.net/socket.php?type...

You need to debug the problem by starting off with only the router plugged into the inner socket on your master. While the faceplate is off disconnect any ringwires on terminal #3 then start adding phone/filters one by one.

Get it fixed sooner rather than later or the BT DLM will kick in and increase your target margin condemning you to slow speeds for ages.

Thanks for the replies

I have two sockets in the flat. In one room a cable emerges from the floor and connects to an old style master socket (but no extension leaves this) in another room a cable emerges from the floor and connects to an extension socket. The ADSL router is plugged in here.

I took the front off the master socket and found the orange/white connected to terminal 1 (which I thought was never used). I snipped it and the broadband went up to full speed - but it did not last. I snipped cable 1 from the extension and put it all back together, but the interference was back and I cannot get rid of it (I even tried reconnecting cable 1 in the extension just to see).

If I move the connectors in the master socket around the broadband gets better and worse.

Could it be a faulty master socket? It's on a cold damp wall and the metal of the connections looks a bit corroded (I re-did the connections but it did not help).

In reply to Backpack's question, the stats are taken from a problem period but cover 24 hours where it was bad, fine then bad again.

What should I do next?

Edited by Lumo (Mon 09-Feb-09 22:09:24)

In reply to a post by Lumo:

If I move the connectors in the master socket around the broadband gets better and worse.

Could it be a faulty master socket? It's on a cold damp wall and the metal of the connections looks a bit corroded (I re-did the connections but it did not help).

I think we have a winner there. From your description it's time to try and get an engineer on site to replace the master socket.

Do you get any noise problems on normal voice calls? If so, book a voice fault.

NOTE: This would usually be a chargeable visit

Try the modem direct into the test socket, if that is good then its a wiring or faceplate issue which you can replace cheaper yourself

I changed the master socket (which is the old type without a faceplate hiding a test socket) and extension socket but this made no difference at all. Voice calls are fine with no crackle or noise. It would be very hard to check the rest of the internal wiring as it is under floorboards.

The ADSL is fine during the day but gets progressively worse in the evening and night - does this indicate anything? I've checked that things like central heating aren't causing the problem.

What should I try next?

When you have the new faceplate disconnected, one assumes none of the extensions work? If they do, then you need to find out how that is wired in