[asterisk-bugs] [Asterisk 0016665]: DTMF not detected at all from Sipgate despite TCPDump showing keypresses

[Asterisk Bug Tracker]

A NOTE has been added to this issue. 
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https://issues.asterisk.org/view.php?id=16665 
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Reported By:                d_richards
Assigned To:                
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Project:                    Asterisk
Issue ID:                   16665
Category:                   Core/RTP
Reproducibility:            always
Severity:                   major
Priority:                   normal
Status:                     acknowledged
Asterisk Version:           1.6.2.1 
JIRA:                       SWP-775 
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:             2010-01-21 03:29 CST
Last Modified:              2010-01-28 15:02 CST
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Summary:                    DTMF not detected at all from Sipgate despite
TCPDump showing keypresses
Description: 
V: 1.6.2.1

Issue is with incoming calls from ITSP 'Sipgate'. DTMF keypresses are not
detected when they enter Sipgate from the PSTN network, despite being
clearly visible with a TCPDump. There are some very slight differences in
the events:
(this may help to visualise:
http://www.fotobytes.co.uk/user22171/dtmf_debug.php )

WORKING DETECTION:
1... .... = Marker: True
Payload type: telephone-event (101)
..00 0000 = Volume: 0
Event Duration: 480

FAILED DETECTION:
0... .... = Marker: False
Payload type: Unknown (101)
..00 1010 = Volume: 10
Event Duration: 1280

Initially considered this to be config/Sipgate but after several weeks of
tweaking, changes, reading up and consultation with Sipgate this looks like
Asterisk could be to blame. Have tried with Linksys ATA and it detects the
DTMF coming in from Sipgate flawlessly, which tends to support the issue is
at least partially with Asterisk.
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 (0117333) lmadsen (administrator) - 2010-01-28 15:02
 https://issues.asterisk.org/view.php?id=16665#c117333 
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I think this is the issue...

Payload type: telephone-event (101)   vs.    Payload type: Unknown (101)

Its my belief that the gateway that SIPgate is using is not declaring the
payload type correctly, and because of this Asterisk doesn't know what is
going on with the DTMF (or that its DTMF at all?).

Because Asterisk should be RFC compliant, I'd like to see where it says in
the RFC that we should be able to accept this type of payload type and know
what it is. 

Issue History 
Date Modified    Username       Field                    Change               
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2010-01-28 15:02 lmadsen        Note Added: 0117333                          
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