[Asterisk-Users] TDM400P static on call

[Derek Lee-Wo]

I just got a TDM400P with 2 FXO cards.  I got it all configured and I
can place and receive calls.

I seem to be getting static on the call, mainly when I speak.  E.g, if
I call someone, I can hear them just fine, but they would hear static.
 Not a lot...more like a constant background "hissing" noise.

What can I look at to try and troubleshoot what is going on, or is this normal?

I played with the rx and tx values, but it didn't seem to make much difference.