Question : Incoming DTMF tones on Trixbox 2.6 too short.

We have a Trixbox 2.6 installation with a ZAP analog trunk and a SIP trunk.  When someone calls in to our system using either of these trunks and they try to dial an extension on our IVR menu, sometimes it does not work and they have to either call again or mash buttons until something goes through.  

I've tried testing this out by calling in to a line on the phone system with my cell phone and dialing numbers on my cell.  On the inside phone, I hear a short "clipped" tone about a few milliseconds long, a short half second pause, and then a 1 second tone.  This happens on both the analog and SIP trunks (which means it's a configuration issue) and is probably the cause of why the IVR gets confused sometimes.   What can I do to get these incoming DTMF tones to play properly?

Thank you

Answer : Incoming DTMF tones on Trixbox 2.6 too short.

Have you tried "relaxdtmf" setting in zapata.conf ?

http://www.voip-info.org/wiki/view/Asterisk+config+zapata.conf
relaxdtmf: If you are having trouble with DTMF detection, you can relax the DTMF detection parameters. Relaxing them may make the DTMF detector more likely to have "talkoff" where DTMF is detected when it shouldn't be. Default: no.
relaxdtmf=yes