Summary:ASTERISK-00126: TDMXX does not correctly pass DTMF after Dial Command
Reporter:capouch (capouch)Labels:
Date Opened:2003-08-19 14:22:30Date Closed:2004-09-25 02:46:18
Versions:Frequency of
Description:This bug is documented in the archives.  Once a call has been dialed using TDMXX device something is wrong with the DTMF tones asterisk sends; they are not intelligible as such to processors at the other end of the call.
Comments:By: Mark Spencer (markster) 2003-08-20 01:56:02

Have you called Digium technical support about this issue?

By: Mark Spencer (markster) 2003-08-20 15:23:42

If the TDMXX is connected to the phone and the user is dialing digits, how does it get to the far end device?

By: Mark Spencer (markster) 2003-08-23 13:50:18

Customer seems to have disappeared.

By: Mark Spencer (markster) 2003-08-24 10:48:38

Please provide details here about your your problem.  Specifically, can you describe the architecture of what you have and what isn't getting to the far end?

By: capouch (capouch) 2003-08-24 11:23:04

The quality of the DTMF tones generated by the TDM card appears to degrade once a call has been set up.

http://lists.digium.com/pipermail/asterisk-users/2003-July/015960.html describes the problem.

I use an AT&T calling card of the "call an 800 number first" design.  For many months it worked just fine.  Now if I dial the access number and wait for the channels to bridge, the remote equipment cannot then discern the DTMF digits properly.

Workaround is to embed the full set of digits-to-be-dialed into the original Dial command interspersed with waits.

By: Mark Spencer (markster) 2003-08-24 14:49:58

Again, can you confirm the architecture?  Am I to assume your call originates on a TDM10B or similar and terminates on an X100P?

By: capouch (capouch) 2003-08-24 16:06:15

TDM20B, talking to any one of a variety of instruments.  Asterisk running on a 450Mhz PII, X100P (Actually I think it identifies as a X101P) talking to a POTS line.

By: thunderz (thunderz) 2003-09-18 20:43:48

I have similar problem with TE410P and T400P, which are connected to another IVR system via T1 crossover.  With the CVS in the past few months, whether I ring in via PSTN or channel bank, DTMF will not be detected properly on the remote IVR system (missing digits).  The CVS version in April doesn't seem to have this problem.

This problem also applied to E1 crossover about a few weeks ago, the current CVS works fine with E1 crossover though.

The workaround I use now, is to bridge an IAX session in the middle, so PSTN (CB) -> IAX -> T1, this way no problem with DTMF at all.

By: capouch (capouch) 2003-09-29 02:23:12

Don't know what fixed it, but tonight "just for fun" I tried duplicating the earlier behavior, and it now seems to work just fine.

I don't know if this will be true for others, but I spent quite a bit of time playing and in every case the DTMF tones were received just fine.