[asterisk-bugs] [Asterisk 0016750]: Audio loop reports T38 switchover but t38state != T38_STATE_NEGOTIATED

[Asterisk Bug Tracker]

A NOTE has been added to this issue. 
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https://issues.asterisk.org/view.php?id=16750 
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Reported By:                iskatel
Assigned To:                
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Project:                    Asterisk
Issue ID:                   16750
Category:                   Applications/app_fax
Reproducibility:            always
Severity:                   major
Priority:                   normal
Status:                     acknowledged
Asterisk Version:           1.6.2.1 
JIRA:                       SWP-839 
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:             2010-02-02 01:32 CST
Last Modified:              2010-06-08 09:49 CDT
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Summary:                    Audio loop reports T38 switchover but t38state !=
T38_STATE_NEGOTIATED
Description: 
SendFax not working with t38

Path of call
Asterisk(1.1.1.1) -> Cisco AS5300(2.2.2.2) -> PSTN

app_fax.c was applied from
http://svnview.digium.com/svn/asterisk/branches/1.6.2?view=revision&revision=225871

After re-INVITE has been received from Cisco, asterisk sends 200 OK, then
ERROR appears and asterisk breaks the call. ReceiveFax works.    

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 (0123111) alexr1 (reporter) - 2010-06-08 09:49
 https://issues.asterisk.org/view.php?id=16750#c123111 
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I can send faxes successfully from the 1.6 machine thru the 1.4 machine to
a T38Gateway, but not from the 1.6 machine thru the 1.4 machine back to the
original 1.6 machine. (Internal users faxing each other).

It results in the error: Audio loop reports T38 switchover but t38state !=
T38_STATE_NEGOTIATED

Trying to send from AST1.6.2.8 to AST1.4.25(passthru) back to the same
AST1.6.2.8 machine. (These two machines have 1 trunk between them with ONLY
ulaw enabled)

I noticed things like
"Have T.38 but no audio"
and
"Done building SDP. Settling with this capability: 0x0 (nothing)."

Both ends fail to get to T38 mode and end up in Audio mode but then fail
after "Transmission Error". Of course, it is hard to tell the sending and
receiving CLI messages apart because they are both on the same box, so
tomorrow I'll setup a 2nd box and attempt to replicate it on there (and
capture distinct, separate CLI outputs of SENDING & RECEIVING ends)

I'm sending the faxes from call files which look like this:
Channel: Local/1731 at fax-out
WaitTime: 30
Maxretries: 0
RetryTime: 30
Callerid: Fax<60001>
Set: LOCALSTATIONID=0700000000
Set: LOCALHEADERINFO=
Set: T38CALL=1
Set: T38TXDETECT=yes
Set: FAXFILE=/tmp/sendfax/1731.tif
Set: FAXID=1731
Context: fax-send
Extension: s
Priority: 1
StartRetry: 8202 1 (1275985281)

I'm not sure if it is related to the existing issue. 

Issue History 
Date Modified    Username       Field                    Change               
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2010-06-08 09:49 alexr1         Note Added: 0123111                          
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