[asterisk-users] Clarification on DAHDI Fax Detection

[Tom Rymes]

Hi folks,

I was hoping that someone might be able to help clarify some confusion I 
have on DAHDI Fax detection after spending some time searching. My 
understanding is this:

1.) Echo cancellation is automatically disabled upon recognition of a 
CNG tone, regardless of the faxdetect setting. This can only be disabled 
at compile time.
2.) faxdetect=incoming will, upon detection of a CNG tone, send the call 
to the fax extension.
3.) faxdetect=outgoing will ??????

Also, do Digium cards with HW Echo Cancellation detect the CNG tones in 
hardware? If so, how does the faxdetect setting in DAHDI affect that 
behavior?

Many thanks,

Tom