[asterisk-users] Echo Cancelation

[Robert Boardman]

Hi All

I Have an ISDN 30 circuit passing through an asterisk box to a legacy 
pbx, all is working well but I have had a problem that modems do not 
work, I thought of turning off echo cancelation but I cann t seem to 
find the ial switch do do it, could someone point me in the right 
direction to enable /disbale ec on a zap channel per call?

Thanks
Robb