[asterisk-dev] Dropping incompatible voice frame

[Joseph Rothstein]

I have opened this discussion on the users forum but got no response so I
thought I would try here.

I am seeing this error quite often on one of our Asterisk boxes:

Feb  6 10:27:15 NOTICE[12642] channel.c: Dropping incompatible voice frame
on Local/944 at sanset-021d,2 of format slin since our native format has
changed to alaw
Feb  6 10:27:15 NOTICE[12642] channel.c: Dropping incompatible voice frame
on Local/944 at sanset-021d,2 of format slin since our native format has
changed to alaw
Feb  6 10:27:15 NOTICE[12642] channel.c: Dropping incompatible voice frame
on Local/944 at sanset-021d,2 of format slin since our native format has
changed to alaw

The problem lasts about 6-10 seconds, and produces several hundred error
lines.

I am not sure if anything in particular triggers this as I am reluctant to
add verbose logging to my log file for fear of impacting performance.

The SIP phones being used are SNOM 320s. I have also opened a ticket with
SNOM, and have submitted traces to them, but the trace does not show any
problem with the RTP packets. They all appear to be sent with the correct
format, g729. G729 is the only codecs enabled in sip.conf as well as on the
phones themselves.

I really have no idea how to progress in solving this, especially since slin
seems to be Asterisk's native internal codec. I am also not sure what is
producing the 'local' channel as I am not using the lcoal channle in any of
my configuration.

Any ideas would be greatly appreciated.

Regards to all,
Joe