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Community Member

Some outside calls have about a 5-10 seconds of dead air

We have a 2811 that has a channelized t1 for voice coming into a controller t1 wic card. We also have a data t1 coming into the same exact type of card. (Both services have a seperate card). We are running IOS version 12.4(12) Advanced IP Services.

Several times a day calls come in that ring normally. When the receptionist answers the phone, there is about 5-10 seconds of dead air, then the other end says "hello? are you there" and after that happens everything is A-OK. I have talked to the provider and they have run two tests on their lines that tested frequencies and devices and there were zero errors.

When I do a "show controllers t1 x/x/x" there are over 300 slip seconds and this number increments.

Any advice on what to do? IOS upgrade maybe? Thanks in advance...


Re: Some outside calls have about a 5-10 seconds of dead air

Sounds like a clocking problem on your PRI. You need to check and see if the "network-clock- participate wic x" and "network-clock-select 1 T1 x/x/x" are configured on your gateway. That should remedy the issue w/the slipped seconds.

Hope that helps..if so please rate post

Community Member

Re: Some outside calls have about a 5-10 seconds of dead air

Thanks for the response. I noticed that the statement "network-clock-participate wic 1" command is issued along with "no network-clock-participate wic 0"

Here is an update:

I reversed the clock roles with my provider. Meaning, I have issued the command "clock source internal" and they issued "clock source line". They said that they are starting to rack up some slip seconds, but none of our calls coming in have had the lag. This has been lag free for almost 24 hours.

Any advice from here on out?

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