Description
There is a call drop issue that involves Fanvil Indoor Station and Grandstream GXV3350 registered through UCM63XX. Missed calls are shown on the Fanvil SIP Indoor Station. However, a call goes through if it is dialed from GXV3240.
Analysis
We manage to capture the packets from UCM and analyze both good and bad calls from GXV3240 and GXV3350. We can see that UCM returns 488 Not Acceptable Here during the call establishment.
How-to
a. Make sure that the UCM’s Extension settings, Fanvil, and Grandstream endpoints have the matched CODEC
b. After further multiple attempts, uncheck Enable BFCP option under GXV3350’s Web UI > Account Codec Setting > Presentation Setting is able to resolve the call drop issue with Fanvil Indoor Station.
