[Asterisk-Users] SpanDSP: Training failed (sequence failed)

[Steve Underwood]

CClarke wrote:

>Hello All ~
>Having problems sending and receiving faxes with SpanDSP. I am testing on a
>simple 2 analog POTS to 2x X100p set up, connecting one line to a Konica 720
>fax machine to test, or with other remote fax machines. Voice calls are
>working pretty well now. Platform is P3/800MHz/256MB/FC1.
>
>* recognizes faxes, and passes calls to RxFax and TxFax OK, but 99.9% of the
>time no fax content is sent or received. (On one occasion coincidentally a
>  
>
So, you tried at least 1000 tests to get this statistic. Very dedicated. :

>junk fax came in successfully while I was testing!).
>
>I've reviewed previous posts and but can't find any relevant advice on where
>to go next, since the fax negotiation seems to go OK so far, but then die (see
>below), and no content is transmitted. The final error message from RxFax is:
>Training failed (sequence failed)
>
>Would really appreciate some expert advice on what this means and how to
>fix...
>Christina.
>
>PS: Previous somewhat relevant posts I've been able to find:
>http://lists.digium.com/pipermail/asterisk-users/2004-June/051143.html
>http://lists.digium.com/pipermail/asterisk-users/2005-February/090978.html
>  
>
Those don't seem very relevant. There are plenty of posts which are.

>Here's versions I'm using:
>asterisk CVS-v1-0-02/20/05-17:04:48
>spandsp 0.0.1k
>libtiff 3.5.7
>  
>
Try using spandsp-0.0.2pre10. spandsp-0.0.1k is now very old. That 
shouldn't be very relevant to your problem, since the modems in 0.0.1k 
usually decode reliably. The ones in 0.0.2pre10 are more tolerant of 
really bad phone lines, though. Also, I have no intention of supporting 
0.0.1k any more.

The fast modem isn't training properly. A number of people report this, 
and there is nothing I can do about it. They have problems in their * 
setup, which prevents spandsp from getting a clean signal. I really need 
to put a self-diagnosis feature in spandsp so it can detect and report 
these problems.

Regards,
Steve