[asterisk-dev] Double tones sometimes detected with RFC2833

[Bryan Field-Elliot]

We are using Asterisk 1.6.2.6, and have several applications running which are touchtone based and we use RFC2833 exclusively.

For a very small number of clients, we seem to be getting "double tones" every so often, i.e. a "0123" will be transmitted, but our Asterisk app receives "00123".

I don't know what the source is of the extra digits -- perhaps Asterisk is decoding the RFC2833 "0" digit twice, or, perhaps it's processing the RFC2833 "0" digit, and also detecting "0" from the inband audio data at the same time.  99% of the time, this doesn't happen and all is well, but I'm trying to chase down that final 1%.

Does anyone have any ideas about what might be causing this, what we might do to work around it, etc.?

Thank you,

Bryan