Intermittent No Audio Issues

[Timothy]

Hi,

Over the last few months, we have been seeing intermittents problem where no audio is heard on calls inbound. We are using 3CX and T46G phones.

I've been taking packet captures on the phone system and only today I've noticed that when the issue seems to occur, the phone is also send the following Syslog message:

TR9 [1458]: TR9 <3+error > Call fail\n

This error is seen multiple times.
Does this mean anything to anybody? Something to focus on or something to ignore?

We have found a workaround whereby the users place the call on hold and then retrieve the call. After that, both ends have audio.

Hopefully someone can help me.