Dead Air and "Machine Gun" Sound During Calls

[sdbell29]

We have two sites with CS1K's running 5.5 with current patches. Both sites are experiencing this problem. While on a call (TDM or IP)some users are experiencing about 5 seconds of dead air or a "machine gun type sound". When this clears, the call is normal. Sometimes it will happen more than once during a longer call. This has happened with calls set to set and calls to external numbers. We have had the data group check for errors on the Cisco switches connected to each MGC with no significant errors. I have cross referenced the times of the occurances and there are no errors on the switch realated Any suggestions would be appreciated. Thanks

 

[bigindian65]

if loadware is current on MGCs and SS, I'd cycle power.

Mato' Was'aka

 

[DFKSydney]

Have you checked the clocking LD 60???

Could be that you are getting slippage.

 

[sl1input]

Does it happen on internal IP > IP phone on same switch??

If it does happen IP > IP then its not a DSP/MGC issue.


Does it happen on internal TDM > TDM on same Media Gateway or same card ??



Are the TLAN & ELAN in separate subnets and separate VLAN's. Are they separate from normal PC subnet / VLAN ?

 

[sdbell29]

Thanks for the replies....

bigindian65 - we have not powered down but did do an INI recently at one of the locations with the same results.

DFKsydney- originally we did check for clocking errors until we realized the problem was happening set to set on the same switch.

sl1input
- it does happen set to set on the same switch...tdm to tdm, ip to ip and tdm to ip.

- the TLAN and ELAN are seperated from each other and other data
traffic

I am going to setup a call today between two phones and put a sniffer on the two DSP resources that are being used to see if I can duplicate and catch the problem. It has been random across both sites and not easily duplicated.