[asterisk-users] channel.c switches to gsm even when sip.conf only allows ulaw

[Jonas Arndt]

Hi Guys,

I have noticed a weird behavior in 1.4.12. When using Authenticate or
DISA in the dial plan the channel immediately switches to gsm format (if
you request a password) or slim (if you run DISA without password). The
debug log says...

===============================
[Oct 14 21:23:00] DEBUG[9013] channel.c: Set channel
SIP/1970xxxxxx-0821aad0 to write format gsm
[Oct 14 21:23:00] DEBUG[9013] rtp.c: Difference is 82008, ms is 10271

===============================

It does this without caring about the fact that you are ONLY allowing
ulaw in the channel configuration. I have so far played with SIP but it
seems the behavior is there for other channels as well (briefly tried it
on IAX as well)

The problem with this is that some SIP providers (ViaTalk) only allows
DTMF of the type inband, which only works on ulaw. Therefore this switch
to GSM makes it impossible to enter the DISA or Authenticate password.

This behavior seems to have been introduced with 1.4.12 as I didn't have
any problem in 1.4.11. Has somebody else seen this.

Cheers,

// Jonas