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New Member

Static only when talking on IP Phone

Hello All,

We have a 7835 running CM 3.2.3. Our IP Phones are using load P00303020700, and our gateway is a 5350 running C5350-IS-M, 12.2(15)T. We have turned off VAD, Comfort Noise on the 5350 and Silence Suppression on the CM.

Our problem is that when someone makes an outside call on any of the IP Phones they hear static only when they talk. When the PSTN party talks or there is silence there is no static.

Has anyone experienced a simliar problem and what is the fix?

Thanks for your help.


Re: Static only when talking on IP Phone

I would strongly suspect timing synchronization on your voice T1s. Check for frame slips on both ends.

New Member

Re: Static only when talking on IP Phone

We have checked our PRI's and there are not slips of any type. Additionally, we have a VG200 that connects a traditional PBX to the voip network and calls from it out the PRI's don't have the static. It only appears on voice calls from 7900 phones thru the gateway.