Is your PRI on the same controller as the phones?
yes it is. I will also mention we did not create 2 VLANs, one data and one voice...and not QOS on the closet switches. I am planning this out as Mitel has this listed as one of the top 5 things that should be done on an install.
If yes, you're going to have to have the carrier look deeper in to the problem (good luch with this).
I've see it where there is a problem in their network but the PRI to your location is good.
So when they test the PRI they only test the local loop.
You're going to have to try and find a way to duplicate it in some fashion so the carrier can do a trace.
I have a ticket issued with them they have done non-destructive testing on each trunk with a CLEAN response (go figure). I heard perhaps a busy out on each trunk one by one testing would offer some helpful info.
However....
Next time someone get's no audio, put the call on hold and take it back off again to see if that resolves. If it does, then it's your PBX.
I will test this....excellent suggestion.
My interconnect also said to put the Mitel IP Phone analyzer on it and watch for excessive packet loss. I have that running and I noticed larger drops on each call.
Appreciated Ralplh.