Asterisk ss7 audio sending & receiving problem

Dear All,

I have installed and configured ss7 on asterisk-13.Some channels are working fine but nothing hear audio on some channels. I have tried to monitor on those channels by dahdi monitor 33 -v. Please see the below log:

Visual Audio Levels.

Use chan_dahdi.conf file to adjust the gains if needed.

( # = Audio Level * = Max Audio Hit )
<----------------(RX)----------------> <----------------(TX)---------------->
###################################* Rx: 0 ( 0) Tx: 14915 (15400)

According to the above log, Tx is working. So, audio packet is sending from my end. Rx 0 means, nothing is receiving from telco. but my telco says, they are not getting any audio packet from my end. That means, asterisk is not sending any audio packet. What is the main reason? if telco is right, why is asterisk not sending any audio packet? How to solve it? Please need your support.

Thanking You,