[asterisk-users] Noise on FXS ports (Sangoma)

[Stephen Bosch]

Hi, John:

This feedback is brilliant. Thanks. My comments follow.

John Novack wrote:

> In your case, from listening to the recording, it really seems as if it
> is being generated within the card. To be sure, if you haven't already,
> connect to the FXS port directly from a telephone with one of the
> Sangoma provided cables that adapt the 4p modular handset jack to a 6 p
> telephone jack. That would certainly eliminate ANY external source.

I did this early on. The noise was still present.

You're right, it does seem to be narrowing down to the card, since we've
already replaced the FXS module once.

> I confirmed that the card in a machine with out the Sangoma drivers
> running would result in a card without battery, so you really shouldn't
> hear anything. Stopping Asterisk removed dial tone, but with wanrouter
> running the result is silent battery. The only noise I hear is a VERY
> LOW pickup that seems to be coming from the monitor vertical scan.
> Nothing resembling your hiss.
> I assume you don't have additional hardware to try, which makes
> troubleshooting even more difficult.

As it happens we have another new card set in inventory that we could try.

Someone at Sangoma has this problem before and thinks it's the
mainboard. They want us to try putting the card into another server to
see if it will do the same thing.

It will be easier to try the new cardset first, then switch servers if
that doesn't work.

-Stephen-