[asterisk-users] DAHDI DTMF problem?

[Shaun Ruffell]

On Fri, Jul 06, 2012 at 01:28:01PM -0500, Bill Dunn - VCI Internet Services wrote:
>
> I used the dahdi_monitor to record the audio on the T1 channel of the
> working server and the new server. The audio stream of the working server
> allowed me to hear the audio I heard over the phone call plus the DTMF at
> the very beginning. The audio of the new server was completely messed up. I
> could barely make out the where the DTMF and the audio were in the file. If
> I didn't have a working sample I wouldn't know what it was. And, the
> beginning of the new server sample always contains a hum or tone in it
> whereas the working server does not have that.
> 
> What does this tell me?

Bill, to close out this thread: After logging into your system, I'm
nearly certain you'll need to contact Digium technical support for
assistance if moving the card into a different system doesn't change
the results.

I ran the same commands I ran on your server on a test server of
mine and this is what I would have expected on your server:

  $ cat system.em.conf
  span=1,0,0,esf,b8zs
  e&m=1-24
  loadzone        = us
  defaultzone     = us
  $ modprobe --first-time wcte12xp vpmsupport=0 latency=6 debug=1
  $ dahdi_cfg -c system.em.conf
  $ dahdi_maint -s 1 --loopback localhost
  Span 1: local host loopback ON
  $ patlooptest 1 -t 10 && patlooptest 1 -t 10
  Using Timeout of 10 Seconds
  Going for it...
  Timeout achieved Ending Program
  Test ran 33 loops of 2039 bytes/loop with 0 errors
  Using Timeout of 10 Seconds
  Going for it...
  Timeout achieved Ending Program
  Test ran 34 loops of 2039 bytes/loop with 0 errors

On your server this same sequence would produce repeated patloop
errors even though there were not any indications in dmesg of
latency bumps, which would be case if something else was preventing
the wcte12xp interrupt service routine from running. The patlooptest
errors would explain the bad audio you recorded with dahdi_monitor
and the DTMF
detection problems.

Cheers,
Shaun

-- 
Shaun Ruffell
Digium, Inc. | Linux Kernel Developer
445 Jan Davis Drive NW - Huntsville, AL 35806 - USA
Check us out at: www.digium.com & www.asterisk.org