[asterisk-bugs] [Asterisk 0013209]: DTMF RFC2833 via SIP is not working

[Asterisk Bug Tracker]

A NOTE has been added to this issue. 
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http://bugs.digium.com/view.php?id=13209 
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Reported By:                ip-rob
Assigned To:                
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Project:                    Asterisk
Issue ID:                   13209
Category:                   Channels/chan_sip/General
Reproducibility:            always
Severity:                   major
Priority:                   normal
Status:                     feedback
Asterisk Version:           1.4.21.2 
SVN Branch (only for SVN checkouts, not tarball releases): N/A 
SVN Revision (number only!):  
Disclaimer on File?:        N/A 
Request Review:              
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Date Submitted:             2008-07-31 08:23 CDT
Last Modified:              2008-09-24 22:29 CDT
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Summary:                    DTMF RFC2833 via SIP is not working
Description: 
Using provider bandwidth.com which support RFC2833.  Configure outbound
trunk to use dtmfmode=rfc2833 and we receive double digits on a different
asterisk servers IVR.  American Express IVR does not accept any digits
(used main customer service line to test entering credit card number). 
Other IVR functions do not work.

Changing to inband works but inband should not be required by
bandwidth.com, they support rfc2833.

Configuration is using SIP devices and SIP trunks only.  A search in issue
tracker found similar problems in January of 2008 but no currently open
issues.
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 (0092853) moseby (reporter) - 2008-09-24 22:29
 http://bugs.digium.com/view.php?id=13209#c92853 
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I have similar issues with 1.4.21.1.  Looking at your, and my own, packet
capture files, it appears that the RTP timestamps are changing within a
single telephony event.  From RFC2833, it looks like the RTP timestamp
should reflect the start of the event and be the same in all packets for
that event. In contrast, the duration field is updated every packet.  I
think it is a fair guess to say that some of the  gateways receiving this
are interpreting this change in timestamp as an indication that multiple
key press events have occurred. 

Issue History 
Date Modified    Username       Field                    Change               
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2008-09-24 22:29 moseby         Note Added: 0092853                          
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