FXO Ports - Issue with Static on outgoing

[7532]

We have a site with 6 POTS lines coming in into 2 FXO cards and configured to IP phones (CM 4.1) We are experiencing static only on outgoing PSTN calls. Incoming and on net calls are clear. Checked out the lines through the local carrier, all point to the pbx. We have new cabling and there are 2 FXO's. The chances of both being bad are low. Any suggestions what I should be looking at?

 

[Minue]

Hello
I did not understand your design clearly.So I can say it could be a QOS problem or the router CPU or memory being overload.
Regards

 

[7532]

Thanks for replying Minue, We have several sites all VOIP however this one site has POTS lines terminating on FXO cards and connected to the CM using H.323 on the gateway as a protocol. We are using 7941 phone sets and are experiencing static on outgoing calls. The configuration of these lines are in the voice gateway. So you think this may be a Qos or a memory overload?
Many thanks.

 

[Minue]

Correct me if I am wrong.The IP phones are on the LAN,the CM has the intelligence,the gateway is routing off net calls through the PSTN.
If this is the case it's note likely to be QOS problem.Try checking the CPU and memory load.Also take a look at the codec.Try using the G.711 codec instead of the Cisco default.
Regards

 

[whykap]

Also check your IOS and DSP version on the router. If not current upgrade as there are a lot of bugs related to on board DSP's and the type of behavior you experience.