[asterisk-users] Snom 300 Echo

[Brent Davidson]

We're deploying an asterisk-based phone system at all of our branch 
offices in an effort to eliminate long-distance costs incurred from the 
constant branch to branch calls.  We're using the Snom 300's at all 
offices for the desk phones and X100P cards to interface to 2 analog 
lines.  I'm having a problem tuning all the echo out of the system.  So 
far two branches are using the new system and they are both reporting 
echo on both incoming and outgoing calls.  The echo seems to be confined 
to the Snom 300 phones and is not heard by the person on the zap line.  
The echo is only the voice of the person using the Snom phone.  There 
doesn't seem to be any echo of the analog line audio.  I have tried 
adjusting the gain of the lines, turning on echo cancellation, Turning 
on echo training and nothing seems to work.  At one of the branches, I 
re-compiled asterisk and zaptel using the OSLEC drivers and that doesn't 
seem to have had any effect either.  What am I missing?

Thanks,
Brent Davidson