[asterisk-users] still got ReceiveFax() problem, how to properly setup asterisk fax?

[Kevin P. Fleming]

On 07/27/2012 09:53 AM, Eric Wieling wrote:

> People seem to think that Asterisk won't disable the Echo Canceler when a fax tone is detected.  Why they think that is a total mystery to me,.

Asterisk doesn't do this, the echo canceller itself does (or DAHDI does, 
in some cases). With modern ECs, as well, they don't even get disabled 
when a CED tone (from the answering FAX endpoint) is heard, they instead 
just turn off their non-linear processors, because it's been found 
through years of experience that leaving 'most' of the EC still in place 
makes FAX calls more reliable than if it was completely disabled.

Since the OP has a Sangoma card with an Octasic hardware echo canceller 
on it, he should just leave it alone and let it do its job :-) Turning 
it off is probably making things worse.

Sometimes I wish it was possible to selectively eradicate 'conventional 
wisdom' from the world!

-- 
Kevin P. Fleming
Digium, Inc. | Director of Software Technologies
Jabber: kfleming at digium.com | SIP: kpfleming at digium.com | Skype: kpfleming
445 Jan Davis Drive NW - Huntsville, AL 35806 - USA
Check us out at www.digium.com & www.asterisk.org