Calls from the PSTN breaking up.

[dfarquharson]

I got a ICS7750 running CM3.3 with the 8FXO MRP300. When calls come in to the 7960 with 7914 expansion modules, the voice is choppy. Anybody knows what could be the cause of this?

[Daniel Baum]

What version of IOS is on the MRP300? Network congestion occuring?

Are calls from IP Phone to IP Phone NOT choppy? Are calls via the 8FXO, only the calls that are choppy?

Choppy Voice

Symptom—Choppy voice describes the sound when there are gaps in the voice. Syllables appear to be dropped or badly delayed in a start and stop fashion.

Cause—Common causes are consecutive packets being lost or excessively delayed such that DSP predictive insertion cannot be used and silence is inserted instead. For example, delay inserted into a call through contention caused by a large data packets.

Please see this document to help define the issue you are experiencing. See "Choppy Voice":

http://www.cisco.com/en/US/tech/tk652/tk698/technologies_white_paper09186a00801545e4.shtml

Dan