[Walford58]

I have a minor problem - not sure if anyone else experiences it:
Firmware 5.1.9 on the SPA9000 and 1.0.1.4 on the SPA400. All in the UK.
During a conversation using the PSTN link, the party at the PSTN end hears the occasional DTMF tone. It sounds as if a button is pressed on the handset, but this is not happening.

Normally this occurs when the FXS1 port is in use at the PBX end.
I'm sure it has something to do with the audio configuration on the FXS tab, but I can't think which fields may affect it.

Can anyone please suggest where to look?

Thanks

[jpennell]

Did you ever get resolution to this? I have tried various parameters with no effect...

It only affects calls on the FXS port of the SPA9000 and happens regardless of whether the call is routed via the SPA400 or direct to ISP. I would hazard a guess it is an issue with the 9000.

I doesn't seem a "regular" thing - not like every 30 seconds, more that it occurs when the internal FXS user is speaking and maybe their voice reaches a certain pitch or volume?

[jpennell]

Maybe something, maybe nothing.

I have noticed that the DTMF tone seems to occur when the FXS user is speaking - and at a certain pitch/volume too.

I tried reducing the output and input gain on the regional settings and this seems to have stopped the issue.

Maybe the gain for the FXS has increased in 5.1.9/5.2.5 - the DTMF appears to occur at the same time that the amplitude is "clipped".

[Walford58]

I think you may be on the right track here.
I get the tone only when a female is using the FXS port. Also since I upgraded to 5.2.5 although the tone seems to be slightly less frequent, the volume of it is uncomfortably loud instead of just irritating, so you may well be right about the gain changes between firmware revisions.

[jpennell]

Thinking about it - I haven't had the problem with a mail caller/callee using the FXS either!

I have set DTMF detection mode to Strict and the Input/Output gain to -6 and the problem seems to have gone away...

Let me know how you get on...

BTW, I'm not sure that the DTMF detection mode has anything to do with this - i just realised that i had changed it from normal before i changed the in/out gain.

Regards, J.