Summary:ASTERISK-17585: Fax detection always jump to the fax extension
Reporter:Igor Nikolaev (microlana)Labels:
Date Opened:2011-03-21 06:49:55Date Closed:2011-06-07 14:00:47
Versions:1.8.3 Frequency of
Description:We set up faxdetect=incoming into the chan-dahdi.conf and faxdetect = no into the sip.conf

This settings is not work as expected by the Asterisk documentation.
As described at documentation, DAHDI fax detection must be worked only if call the Answer() application before Dial() application.

But if we got incoming voice call from the DAHDI ISDN PRI, then immediatly (i.e. w/o Answer()) call a Dial() application to the SIP extension by Dial(SIP/003110,30,tTkK) and then start a fax machine on originated side, the Asterisk detect a fax-tone and jump to a fax-extension.

Comments:By: Leif Madsen (lmadsen) 2011-04-01 13:55:55

I'm pretty sure the fact that you enabled the t, T, k, and K options to Dial() caused the channel to be immediately answered, because those flags cause Asterisk to listen for DTMF during the call, which I think requires the channel to be answered.

Which documentation refers to the fax extension not being triggered if there is no Answer()? That sounds wrong to me.