Asterisk 13 outb Dahdi call rings, but callee has to shoout

Hello,
Please help with the following:
We are setting up an Asterisk 13 server.
Asterisk 13 outb Dahdi call rings, but callee has to shoout very, very loud for Asterisk to flag the call as connected (answered).
Many times the calls are not connected (answered).
txGain and rxGain were set to 5.

Appreciate your comments.

tks

Sorry for also posting before in the General Forum.