Problem

After a call is put on hold, the call may drop after 10 seconds in certain instances. This does not happen always. Dropping calls could happen due to missing audio towards the caller/callee. When audio is missing certain networks send a BYE towards the trunk after x amount of time (mostly 10 seconds). The reason for dropping the call are Cellular phones working on VOLTE 4g calling. A timer runs when no audio is received, when no audio is received for 10 seconds the call will drop.

Solution

Add client music on hold when holding a call.

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