Hi All I have an Asterisk server with two PRI's into a Samsung DCS500 which in turn has 4 PRI's into the Telco. I have echo on some calls only over 500km away. I have set: echocancel=yes echotraining=800 echocancelwhenbridged=yes rxgain=1 txgain=-1 Volumes on the ZAP channels are set correctly. Echo problems in the past have been straight forward to remove with the correct echotraning and volumes set. I am quite certain it is due to calls going through the Samsung. Any ideas? Kind Regards Garth