[asterisk-bugs] [Asterisk 0016793]: T38 flow states HDLC carrier immediately down when writing TSI to fax, but were up

[Asterisk Bug Tracker]

The following issue requires your FEEDBACK. 
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https://issues.asterisk.org/view.php?id=16793 
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Reported By:                rlr2maverick
Assigned To:                
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Project:                    Asterisk
Issue ID:                   16793
Category:                   Applications/app_fax
Reproducibility:            always
Severity:                   major
Priority:                   normal
Status:                     feedback
Asterisk Version:           1.6.1.14 
JIRA:                        
Regression:                 No 
Reviewboard Link:            
SVN Branch (only for SVN checkouts, not tarball releases): 1.6.1 
SVN Revision (number only!):  
Request Review:              
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Date Submitted:             2010-02-09 09:10 CST
Last Modified:              2010-02-10 14:38 CST
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Summary:                    T38 flow states HDLC carrier immediately down when
writing TSI to fax, but were up
Description: 
Good morning,

our setup is based on asterisk 1.6.1.14 & spandsp 0.0.6-pre17. We're
always receiving fax with no error.

When sending we're experiencing a quite strange chan_sip codecs
negotiation, selecting ulaw (8kbit??? with fax @14400 ???) even if slin is
preferred and available.

At the first write (TSI) from asterisk to the channel remote side (fax)
we're encountering HDLC carrier down and the transmission never takes
place.

T38 nego can't proceed and fax is never sent.

Is there any experience to share ?

Indeed,
RLR
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 (0117960) lmadsen (administrator) - 2010-02-10 14:38
 https://issues.asterisk.org/view.php?id=16793#c117960 
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You may also want to check the 1.6.1.15-rc2 that was just released to
determine if the couple of T.38 changes that went in there may resolve this
for you.

You'll need to provide a SIP trace and SIP history of this happening as
well in order for a developer to review the issue. 

Issue History 
Date Modified    Username       Field                    Change               
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2010-02-10 14:38 lmadsen        Note Added: 0117960                          
2010-02-10 14:38 lmadsen        Status                   new => feedback     
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