[asterisk-users] Increase DTMF Tone Duration

[Andres]

Hi,

We are running 1.4.22 and have been experiencing problems with certain 
IVRs and DTMF Tone duration.  We would like to be able to increase DTMF 
Tone duration by 50 to 100ms over what the user is pressing on his 
phone.  We have a PRI test circuit and an analyer in between to measure 
tone duration.

We have tried setting chan_dahdi.conf parameter 'toneduration', but that 
does not do anything that we can measure.
We have also tried setting channel.c parameter #define 
AST_DEFAULT_EMULATE_DTMF_DURATION 200
to several different values but none seem to alter DTMF duration at all. 

Does anybody have a clue where we can hardcode DTMF duration for tones 
going out of a DAHDI Channel to the PSTN? 

So far we have to tell customer to 'press the buttons' for a little bit 
longer and it will work with the IVRs in question, but many complain 
saying that they don't have to do that with their regular landline or 
cellphone.

Thanks,
Andres
http://www.telesip.net