[asterisk-bugs] [Asterisk 0015024]: DTMF is not working correctly for cell phones.

[Asterisk Bug Tracker]

A NOTE has been added to this issue. 
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http://bugs.digium.com/view.php?id=15024 
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Reported By:                alexo
Assigned To:                
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Project:                    Asterisk
Issue ID:                   15024
Category:                   Channels/chan_dahdi
Reproducibility:            always
Severity:                   major
Priority:                   normal
Status:                     feedback
Asterisk Version:           1.4.24 
Regression:                 No 
SVN Branch (only for SVN checkouts, not tarball releases): N/A 
SVN Revision (number only!):  
Request Review:              
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Date Submitted:             2009-05-03 15:12 CDT
Last Modified:              2009-05-07 08:52 CDT
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Summary:                    DTMF is not working correctly for cell phones.
Description: 
We have an issue calling the extension number from cell phones. Sometime is
works, but mostly fails.

The problem is that DTMF tones are coming as doubles or just in wrong
order. I'll attach asterisk console output for cell phones and land one
(yes, land phones works as expected - always).

Any help is really appreciated as most of our customers are mobile.
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Relationships       ID      Summary
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related to          0014815 [patch] DTMF Appears to be broken from ...
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 (0104354) alexo (reporter) - 2009-05-07 08:52
 http://bugs.digium.com/view.php?id=15024#c104354 
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Interesting point. rxgain was set to 0 (default) and listening few samples
recorded with voice I noticed same distortions - amplitude drops to zero
several times during sample duration.

This is what I done so far:

1. Migrated from zaptel to dahdi kernel driver (that should be done anyway
to support future upgrades and to avoid possible bugs still present in
zaptel driver).
2. Played with rxgain in chan_dahdi.conf.

There few notices. When I decreasing rxgain (I was trying up to -3.0) the
voice record with dadhi_monitor showed distortions and voice sounded like
robot's one (checked, it wasn't the robot :) Increasing the level (I was
trying up to 2.0) gave me more human-like voice. I can say it sounded very
close to original.

But it all tests DTMF amplitude didn't change at all. Was I using wrong
parameter to tune or why tone signal wasn't changed? 

Issue History 
Date Modified    Username       Field                    Change               
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2009-05-07 08:52 alexo          Note Added: 0104354                          
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