Phone call causes ADSL to drop out?

Has anyone had a similar problem to this:

Since BT OpenReach did some work outside of my house a couple of months
ago, my BB bandwidth has dropped from 5-6.5 Mb/s to 2-3 Mb/s, and as low
as 512Kb/s at times.

When making a phone call, the sound of the router negotiating can be
heard (sounds much like an analogue modem), albeit very feintly.

Making a phone call on the same line causes the ADSL link to drop. I
have two ADSL filters on different junction boxes and I get the same
result on both.

I'm just wondering if this is a known issue - i.e. BT cocking something
up which causes the phone to interfere with the BB. BT phone people say
they've checked the line and it's OK and to contact my ISP. However, I
want to be fully clued up before braving the script-driven Indian call
centre.

TIA
Biggles
(Remove packing from my address to e-mail me)

Biggles wrote:
> Has anyone had a similar problem to this:
>
> Since BT OpenReach did some work outside of my house a couple of months
> ago, my BB bandwidth has dropped from 5-6.5 Mb/s to 2-3 Mb/s, and as low
> as 512Kb/s at times.

Looks like they tired to squeeze more traffic to one line.

>
> When making a phone call, the sound of the router negotiating can be
> heard (sounds much like an analogue modem), albeit very feintly.

Thats strange, because ADSL splitter (in fact simple passive low-pass
filter) should filter out higher frequencies coming to phone from ADSL
modem.

>
> Making a phone call on the same line causes the ADSL link to drop. I
> have two ADSL filters on different junction boxes and I get the same
> result on both.
>
> I'm just wondering if this is a known issue - i.e. BT cocking something
> up which causes the phone to interfere with the BB. BT phone people say
> they've checked the line and it's OK and to contact my ISP.

From symptoms I would say that bandwidth used by ADSL modem and phone
line overlaps. I would be very skeptical about phone company changing
standard ADSL bandwidth to something other than 25.875 kHz.

What I would do:
1) Test if your splitter is OK. Go to a friends house and use @ his ADSL
line.
1.1) If you can hear *his* ADLS modem dialing - your splitter malfunctions.
1.2) If you can't hear his ADSL modem dialing - splitter is OK, *your*
ADSL model malfunctions and uses frequencies other than predefined.

I would bet for bad splitter.

However, I
> want to be fully clued up before braving the script-driven Indian call
> centre.
>
> TIA
> Biggles
> (Remove packing from my address to e-mail me)

"Justin P" <jp|@|nospam.seminte.lt> wrote in message
news:481576fe$0$643$(E-Mail Removed). ..
> Biggles wrote:
>> Has anyone had a similar problem to this:
>>
>> Since BT OpenReach did some work outside of my house a couple of months
>> ago, my BB bandwidth has dropped from 5-6.5 Mb/s to 2-3 Mb/s, and as low
>> as 512Kb/s at times.
>
> Looks like they tired to squeeze more traffic to one line.
>
>>
>> When making a phone call, the sound of the router negotiating can be
>> heard (sounds much like an analogue modem), albeit very feintly.
>
> Thats strange, because ADSL splitter (in fact simple passive low-pass
> filter) should filter out higher frequencies coming to phone from ADSL
> modem.
>
>>
>> Making a phone call on the same line causes the ADSL link to drop. I
>> have two ADSL filters on different junction boxes and I get the same
>> result on both.
>>
>> I'm just wondering if this is a known issue - i.e. BT cocking something
>> up which causes the phone to interfere with the BB. BT phone people say
>> they've checked the line and it's OK and to contact my ISP.
>
> From symptoms I would say that bandwidth used by ADSL modem and phone
> line overlaps. I would be very skeptical about phone company changing
> standard ADSL bandwidth to something other than 25.875 kHz.
>
> What I would do:
> 1) Test if your splitter is OK. Go to a friends house and use @ his ADSL
> line.
> 1.1) If you can hear *his* ADLS modem dialing - your splitter
> malfunctions.
> 1.2) If you can't hear his ADSL modem dialing - splitter is OK, *your*
> ADSL model malfunctions and uses frequencies other than predefined.
>
> I would bet for bad splitter.
>
Mmm, that's probably worth a go. But as I said I have two filters on
different junction boxes and I get the same results on both. I figure if the
symptoms suggest a bad splitter or signal problem then if both splitters
show the same symptoms it's a signal problem - and BT Openreach doing work
outside of my house sounds like *too* much of a coincidence.

Biggles