Paging Causes One-way Audio Silence

[cruz278]

Hi Everyone,

I have this issue we or our third party Avaya supporters can't seem to completely fix. The issue intermittently occurs when anyone user page causes any call that are already connected to lose audio one way (from customer to us) for as long as the page is active. When they lose audio the call becomes completely silent and the other part is not heard. Then when the page ends the call resumes audio both ways. So the call isn't lost at all just the audio one way momentarily until the page stops. My one QoS change to the 46xxx settings txt file helped allot because those settings weren't implemented yet since they were in use with our old Mitel PBX. Any help or suggestions would be deeply appreciated. Our IP Office vs is Version 9.1.8.0 Build 172 and we have about 50-100 extensions in use with most of them being on premise and 25% or less being remote workers. The phones in use are 1608's and 9608's. The system codec in place are g711 and g729.

[cruz278]

More info

One more detail the paging is going to a group of 25 extensions that's all.

[mlombardi1]

What's the VCM capacity of your IPO system? A group page to 25 extensions would cause a sudden spike in VCM resources. Use System Status to monitor VCM usage when paging is invoked.

[cruz278]

Good point I'll check that out with a test and get back you. I know how to check this but my question is are the VCM channels linked to the PRI channels our are they seperate unrelated resources?

[cruz278]

I tested and i see that the total channels are 250 and we've only ever used up to 27 in the past day or 2 and never above that. I'll check during high call volume to see if i see the same thing.

[mlombardi1]

Good point I'll check that out with a test and get back you. I know how to check this but my question is are the VCM channels linked to the PRI channels our are they seperate unrelated resources?

VCMs are your call resources. When a phone goes off-hook, a VCM is used. VCM is also used for any TDM to IP conversion, such as when an IP endpoint is interfacing with a PRI. VCMs and PRIs are separate resources but used together.

250 sounds like adequate resources for a 25 phone page but if you find usage is high during peak hours, consider using shuffling (I think IPO calls this direct media) to enable two IP endpoints to exchange RTP directly to free up VCMs after call setup.

[cruz278]

direct media has been enabled for those in the office's that can access the PBX on a local network. From what my search found is that direct media on those that are remote user's wont be or are not needed as they don't impact this, is that true?

[cruz278]

I checked the codec bit usage and compared it to my current P2P pipe between PBX and office. Anything above 23 exts on a page list would supersede pipes capacity. I always had my mind on this just never looked at it in depth since we already have our replacement P2P up which is a fiber 10mb pipe. I just haven't set it up yet. I reduced the page list to 21 exts and no complaints of current conversations being effected.