[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:              2008-09-29 16:44 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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 (0092956) dlynes (reporter) - 2008-09-29 16:44
 http://bugs.digium.com/view.php?id=13209#c92956 
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I thought I would note that I too, am noticing this issue.

When the DTMF comes into my 1.4.18 box via SIP RFC2833, everything is
A-OK.

However, when it traverses to my 1.4.19.1 box via IAX2, I get duplication
of tones.  If I set relaxdtmf=yes on my incoming SIP lines on my 1.4.18
box, by the time the tones make it to the other end of the IAX2 channel, a
number of the digits end up as other digits, not just duplicated.  Without
relaxdtmf=yes, the digits will get the odd repetition.  It doesn't happen
to be as severe as the original poster, but any amount of repetition and/or
corruption is unacceptable.  When someone types in a string of digits, it
should work 100%, 100% of the time.

However, one thing I am noticing different from the original reporter is
that it doesn't work on ULAW with inband, either. 

Issue History 
Date Modified    Username       Field                    Change               
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2008-09-29 16:44 dlynes         Note Added: 0092956                          
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