[Asterisk-Users] DTMF Talk off

[Doug Crompton]

John,

 Well I am certainly not an expert on this. I am using an SPA-3000 and I
have not experienced this. I did have to go to inband on the fxo channel
as rfc8322 did not work for ivr's when using Asterisk. I think you said
you were using a linksys or sipura product for you fxo?? If that is the
case using inband and the ulaw/alaw encoder for the fxo channel might
help. Worth a try I guess. There are some rfc8322 issues that apparently
will be addressed with a rewrite in the next makor version release.

Doug

On Mon, 19 Jun 2006, John Millican wrote:

>
> Doug, I read that post and unfortunately it was not a solution.  I do not
> believe it has to do with interstate as it happens intra state also.  Is
> there any way to make DTMF detection stricter, ie require a longer minimum
> tone length.  Assuming ( yes a dangerous practice) that the human voice will
> not hold a DTMF sequence stable for very long, if I lengthen the minimum
> required length I may be able to minimize the talk off.  What do you think?
> Any suggestions?
> John M
>
> Doug Crompton wrote:
> > Check....
> >
> >
> > http://lists.digium.com/pipermail/asterisk-users/2005-January/078141.html
> >
> > On Sun, 18 Jun 2006, John Millican wrote:
> > > Hello all,
> > > I have seen some chatter again about DTMF.  I see most of the talk about
> > > DTMF around not being able to get an external IVR to recognize digits,
> > > not a big issue for me at this time but sill interesting.  My issue
> > > though, is with talk off on a zap channel.  It seems to be getting worse
> > > or maybe my patience is thinning.  All my calls go out and come in pstn
> > > through an FXO as I do not have high speed available here at home.  My
> > > Current setup is:
> > >
> > > Phone-->PAP2--> * --->PSTN--->Voip number to * at another location(that
> > > has high speed)--->send to VoIP provider
> > >
> > > I read a post about talked about the length of the DTMFish sound.  I also
> > > remeber seing something about relaxdtmf being set to something other than
> > > yes or no, so I looked in chan_zap.c and found  relaxdtmf in many places
> > > but it looked to my inexperienced eye that it could only be set to 'yes'
> > > or 'no', but i did find some mention of tonlength (at line 10858)
> > > followed that to zaptel.c (line 3357) where it said :
> > > if ((tdp.dtmf_tonelen > 4000 ) || (tdp.dtmf_tonelen < 10 ))
> > >     return -EINVAL
> > > Which I am guessing means unless the dtmf is between these 2 values
> > > ignore it. Any ideas what might happen if i increased the minimum time
> > > value? if this is indeed what this is referring to?
> > >
> > >
> > > Zapata.conf:
> > > [channels]
> > > callwaiting=yes
> > > callwaitingcallerid=yes
> > > threewaycalling=yes
> > > transfer=yes
> > > cancallforward=yes
> > > busydetect=yes
> > > busycount=6
> > > echocancel=128
> > > echocancelwhenbridged=yes
> > > echotraining=yes
> > > rxgain=0
> > > txgain=0
> > > immediate=no
> > > context=default
> > > signalling=fxs_ks
> > > channel => 1
> > > <same for channel 2>
> > >
> > > zaptel.conf:
> > > loadzone = us
> > > fxsks=1
> > > fxsks=2
> > >
> > > extensions.conf:
> > > exten => s,1,  NoOp(${CALLERID} time ${DATETIME});
> > > exten => s,2,  Dial(sip/677&sip/666,30,tT);
> > > exten => <a bunch of stuff to do with agi look ups and voicemail
> > > leave/retrieve>
> > >
> > > All very basic and works like a charm except for the talk off.
> > > Thanks in advance to all,
> > > John M
>


"Those that sacrifice essential liberty to obtain a little temporary safety
 deserve neither liberty nor safety."  -- Ben Franklin (1759)

****************************
*  Doug Crompton	   *
*  Richboro, PA 18954	   *
*  215-431-6307		   *
*		  	   *
* doug at crompton.com        *
* http://www.crompton.com  *
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