I'm using a Digium 410P with a single FXO module in my Elastix 1.5.2 system. The card is detected without issue, seems to work - I have also made the following changes: modules.conf: options wctdm24xxp opermode=AUSTRALIA /etc/dahdi/system.conf: loadzone = au defaultzone = au /etc/asterisk/chan_dadhdi.conf: rxgain=9.0 txgain=-6.0 The RX and TX gain values were suggested here. The problem I'm having is that when I ring people, the line sounds a scratchy, and they complain that I am very quiet. I also hear some noise whilst I talk - almost like echo, but not quite. Does anybody have any suggestions for improving this, or alternate config options I can try? The PSTN line is a Telstra line.