[asterisk-bugs] [Asterisk 0018189]: RFC2833 DTMF generation broken due to SSRC change on bridges channels

[Asterisk Bug Tracker]

A NOTE has been added to this issue. 
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https://issues.asterisk.org/view.php?id=18189 
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Reported By:                marcbou
Assigned To:                twilson
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Project:                    Asterisk
Issue ID:                   18189
Category:                   Core/RTP
Reproducibility:            always
Severity:                   block
Priority:                   normal
Status:                     assigned
Target Version:             1.8.1
Asterisk Version:           1.8.0 
JIRA:                       SWP-2473 
Regression:                 No 
Reviewboard Link:            
SVN Branch (only for SVN checkouts, not tarball releases): N/A 
SVN Revision (number only!):  
Request Review:              
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Date Submitted:             2010-10-22 12:13 CDT
Last Modified:              2010-11-30 19:44 CST
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Summary:                    RFC2833 DTMF generation broken due to SSRC change on
bridges channels
Description: 
Since upgrading to the latest 1.8.0-rc, DTMF digits sent over SIP/RTP to
our service provider were no longer being detected.

We analyzed packet dumps, comparing old and new RTP packets being
generated by asterisk.

The difference was tracked down to asterisk 1.8.0-rc now changing the SSRC
value for RFC2833 DTMF digit packets.

If in main/channel.c:ast_channel_bridge() I comment out 

    ast_indicate(c0, AST_CONTROL_SRCCHANGE);
    ast_indicate(c1, AST_CONTROL_SRCCHANGE);

the SSRC no longer changes for DTMF digits and the provider can detect
them again.

However I am not sure if the change doesn't adversely affect other things.
Please advise.

Kind regards,

Marc Boucher



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 (0129226) warlock52 (reporter) - 2010-11-30 19:44
 https://issues.asterisk.org/view.php?id=18189#c129226 
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This still seems to be an open issue because even up to 1.6.2.15RC1 this is
still the same issue. When can we expect a fix in the DTMF SSRC handling
which is obviously wrong according to RFC and is affecting us with our SIP
provider. 

Issue History 
Date Modified    Username       Field                    Change               
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2010-11-30 19:44 warlock52      Note Added: 0129226                          
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