[asterisk-bugs] [Asterisk 0015296]: TDM call over IAX trunk gives choppy audio, SIP call over same IAX trunk sounds fine.

[Asterisk Bug Tracker]

A NOTE has been added to this issue. 
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https://issues.asterisk.org/view.php?id=15296 
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Reported By:                alecdavis
Assigned To:                
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Project:                    Asterisk
Issue ID:                   15296
Category:                   Channels/chan_iax2
Reproducibility:            always
Severity:                   minor
Priority:                   normal
Status:                     feedback
Asterisk Version:           1.6.1.0 
JIRA:                        
Regression:                 No 
SVN Branch (only for SVN checkouts, not tarball releases): 1.6.1 
SVN Revision (number only!): 199300 
Request Review:              
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Date Submitted:             2009-06-09 07:03 CDT
Last Modified:              2009-09-18 18:34 CDT
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Summary:                    TDM call over IAX trunk gives choppy audio, SIP call
over same IAX trunk sounds fine.
Description: 
Testing to an Asterisk 1.4.20 -> Milliwatt application.
Also tested to an elderly 1.6.x r178446M release. same problems.

senarios are as below:

Analog phone <-> FXS-TDM800P/Asterisk 1.6.1.0 <-IAX internet-> Asterisk
1.4.20 Milliwatt App.

SIP phone <-> Asterisk 1.6.1.0 <-IAX internet-> Asterisk 1.4.20 Milliwatt
App.

Analog phone audio sounds very choppy, SIP phone audio sounds fine.

Tried with GSM only IAX trunks, and ALAW only trunks, same result, no
improvement.


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Relationships       ID      Summary
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related to          0015337 Drawn out and static audio on inbound i...
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 (0111027) alecdavis (reporter) - 2009-09-18 18:34
 https://issues.asterisk.org/view.php?id=15296#c111027 
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When silence suppresion is enabled the cisco, it stops packets going
towards asterisk during silence, the Milliwatt application seems to stop
sending packets when nothing comes in.

Surely the Milliwatt app should keep sending packets.

So this leads me to IAX, if packets have jitter getting to asterisk over
the internet, then as reply packets traverse the internet will have more
jitter added, making for choppy audio, with twice the amount of jitter. 

Issue History 
Date Modified    Username       Field                    Change               
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2009-09-18 18:34 alecdavis      Note Added: 0111027                          
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