Very strange line noise problem - expert help pls!

We have a bulldog business connection that until recently worked
perfectly at around 8M down / 512K up. Suddenly around a fortnight ago
we have the auduible ADSL noise on the analogue line and the upstream
bandwidth has cut to a painfully slow 128K. I have tried everything to
resolve this and am totally stumped as to the problem. Diagnosis as
follows-

-This connection is a straight A/B connection form the BT linebox
oustide the house, there are NO extensions, just the master socket

-Have replaced the microfilter with a new one and now with the high
quality XF1 filtered face plate: still get the line noise and bad
upstream

-If I disconnect the ADSL modem (3Com office connect) the line noise
stops

-If I disconnect the phone line, so I have just the ADSL modem plugged
into hte filtered faceplate, I still get the bad upstream.

The modem reports the following:-

Operation Data Upstream Downstream
Noise Margin 7 dB 9 dB
Attenuation 22 dB 19 dB

...and as soon as it has been up for a while I get hundreds of Fast Path
CRC Errors on the Near End Indicator but none on the far end.

I am totally stumped- the noise is definitley coming from the ADSL
modem a if I turn it off it goes, so I think filtration problem - but I
am now on the third filter at the master socket (where everything is
connected) and see no change.

There has been building work going on and I can't guarnatee that things
have not been fiddled with but I have manually inspected the cable run
(CAT6) from the A/B terminals on the master socket to the A/B terminals
on the BT line box (big black thing with room for about 20 phone lines
for the building) and have even changed it over to two different wires
within the CAT6 and have the same problem.

what on earth could it be?

thanks in advance

(E-Mail Removed) wrote:
> We have a bulldog business connection that until recently worked
> perfectly at around 8M down / 512K up. Suddenly around a fortnight ago
> we have the auduible ADSL noise on the analogue line and the upstream
> bandwidth has cut to a painfully slow 128K. I have tried everything to
> resolve this and am totally stumped as to the problem. Diagnosis as
> follows-

Tricky.

Have you tried an alternative router, just to rule that out as failing?
In addition, is your power supply okay? Tried running the router
through a filtered adaptor?

Are ALL devices on the line running through filters?

Alternative router is the next step, will try playing with the power
although I would have thought that a fault there would cause
interference all the time- we only hear the line noise when the ADSL is
synced.

There are no other devices on the line- the modem and the single
telephone are connected directly to the (now master plate filtered)
master socket

(E-Mail Removed) wrote:
> We have a bulldog business connection that until recently worked
> perfectly at around 8M down / 512K up. Suddenly around a fortnight ago
> we have the auduible ADSL noise on the analogue line and the upstream
> bandwidth has cut to a painfully slow 128K. I have tried everything to
> resolve this and am totally stumped as to the problem. Diagnosis as
> follows-
>
> -This connection is a straight A/B connection form the BT linebox
> oustide the house, there are NO extensions, just the master socket
>
> -Have replaced the microfilter with a new one and now with the high
> quality XF1 filtered face plate: still get the line noise and bad
> upstream
>
> -If I disconnect the ADSL modem (3Com office connect) the line noise
> stops

Does this not sound like the HR (high resistance) fault that was recently
discussed here?

Hopefully kráftéé will be along to add his comments.

See
http://groups.google.co.uk/group/uk....1f5a3d4bc3d2ff

or http://tinyurl.com/l8mbs

HTH

Tim

Have you tried plugging directly into the test socket? It is rare, but not
unknown, for the removable faceplate to be faulty. As others have said try a
different router/modem again plugged directly into the test socket.

Peter Crosland

Yes, I've tried directly into the test socket. I have 99% eliminated it
being a socket, filtration or internal wiring problem.

Will try another router on Monday, if it still doesn't work I'm not
looking forward to trying to get this one past bulldog 'support'...

Peter Crosland wrote:
> Have you tried plugging directly into the test socket? It is rare, but not
> unknown, for the removable faceplate to be faulty. As others have said try a
> different router/modem again plugged directly into the test socket.
>
> Peter Crosland

On 12 May 2006 05:52:52 -0700, (E-Mail Removed) wrote:

> Yes, I've tried directly into the test socket. I have 99% eliminated it
> being a socket, filtration or internal wiring problem.
>
> Will try another router on Monday, if it still doesn't work I'm not
> looking forward to trying to get this one past bulldog 'support'...
>
> Peter Crosland wrote:
>> Have you tried plugging directly into the test socket? It is rare, but not
>> unknown, for the removable faceplate to be faulty. As others have said try a
>> different router/modem again plugged directly into the test socket.
>>
>> Peter Crosland

Based on my own recent experience I would suggest you try a different power
supply. I have three 3Com routers at different locations, one 'lost' the
connection after the SNR dropped to 1!

The 3Com plug top PSU was found to be the culprit, if you can find another
with the same voltage, polarity and at least the same current swap them
over, you may have a surprise.

--
Regards
Barry

"BJH" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed)...
| On 12 May 2006 05:52:52 -0700, (E-Mail Removed) wrote:
|
| > Yes, I've tried directly into the test socket. I have 99% eliminated it
| > being a socket, filtration or internal wiring problem.
| >
| > Will try another router on Monday, if it still doesn't work I'm not
| > looking forward to trying to get this one past bulldog 'support'...
| >
| > Peter Crosland wrote:
| >> Have you tried plugging directly into the test socket? It is rare, but not
| >> unknown, for the removable faceplate to be faulty. As others have said try
a
| >> different router/modem again plugged directly into the test socket.
| >>
| >> Peter Crosland
|
| Based on my own recent experience I would suggest you try a different power
| supply. I have three 3Com routers at different locations, one 'lost' the
| connection after the SNR dropped to 1!
|
| The 3Com plug top PSU was found to be the culprit, if you can find another
| with the same voltage, polarity and at least the same current swap them
| over, you may have a surprise.
|
| --
| Regards
| Barry

Have you reported it to your service provider?

"Tim Downie" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed)...
> (E-Mail Removed) wrote:
>> We have a bulldog business connection that until recently worked
>> perfectly at around 8M down / 512K up. Suddenly around a fortnight
>> ago
>> we have the auduible ADSL noise on the analogue line and the
>> upstream
>> bandwidth has cut to a painfully slow 128K. I have tried everything
>> to
>> resolve this and am totally stumped as to the problem. Diagnosis as
>> follows-
>>
>> -This connection is a straight A/B connection form the BT linebox
>> oustide the house, there are NO extensions, just the master socket
>>
>> -Have replaced the microfilter with a new one and now with the high
>> quality XF1 filtered face plate: still get the line noise and bad
>> upstream
>>
>> -If I disconnect the ADSL modem (3Com office connect) the line
>> noise
>> stops
>
> Does this not sound like the HR (high resistance) fault that was
> recently discussed here?
>
> Hopefully kráftéé will be along to add his comments.

Sorry just got back from a boozy weekend, have I missed anything???

To the OP, the 3Com Office Connect routers suffered from a bout of
faulty power supplies causing a problem with the routers (discussed at
great depth in the forum a month or 2 ago), when you are checking
without any synch is the router connected & powered up?.

Builders..... don't trust them, has some work done earlier this year,
pointed out the cables to be avoided at all costs only to find they
had put a nail thru the tele leadin & an extension (not bad for one
nail) & also crushed yet another one for good measure , when patched
got a 50hertz hum, caused by the new electrical cables being run close
by so I had to reroute.

As for the HR connections, been meeting up with them a lot (possibly
due to the damp/muggy weather). All _you_ can do is check & double
check all connections, have the builders crushed the cable (or hit it
with a nail etc) but after cheking your own internal
wiring/connections the only thing you are left with is reporting it to
your service provider, not BT, that way you should get an ADSL
'trained' engineer who may know (or not as the case may be) how to
check out the circuit/copper path back to the exchange. Report it as
a intermitent synch problem & hopefully everything will come up
smelling of roses, or chocolates depending on what takes your fancy..

"Willy Sobigiterts" <(E-Mail Removed)> wrote in message
news:f149g.22667$(E-Mail Removed)...
>
> "BJH" <(E-Mail Removed)> wrote in message
> news:(E-Mail Removed)...
> | On 12 May 2006 05:52:52 -0700, (E-Mail Removed) wrote:
> |
> | > Yes, I've tried directly into the test socket. I have 99%
> eliminated it
> | > being a socket, filtration or internal wiring problem.
> | >
> | > Will try another router on Monday, if it still doesn't work I'm
> not
> | > looking forward to trying to get this one past bulldog
> 'support'...
> | >
> | > Peter Crosland wrote:
> | >> Have you tried plugging directly into the test socket? It is
> rare, but not
> | >> unknown, for the removable faceplate to be faulty. As others
> have said try
> a
> | >> different router/modem again plugged directly into the test
> socket.
> | >>
> | >> Peter Crosland
> |
> | Based on my own recent experience I would suggest you try a
> different power
> | supply. I have three 3Com routers at different locations, one
> 'lost' the
> | connection after the SNR dropped to 1!
> |
> | The 3Com plug top PSU was found to be the culprit, if you can find
> another
> | with the same voltage, polarity and at least the same current swap
> them
> | over, you may have a surprise.
> |
> | --
> | Regards
> | Barry
>
> Have you reported it to your service provider?

Not been keeping up (with the thread) have we....