Hi,

We have a Mikrotik hEX RB750Gr3 5-port Ethernet Gigabit Router, with RouterOS 6.48.2.

We're located in Canada.

We had a new Panasonic VoIP PBX (NS700) in house installed by a firm that does just that, 6 months ago.
All the port forwarding were set in the Mikrotik router according to their specifications.
Since then we have the following trouble:
It's always the same person who answer the calls of the business. 2 to 5 times a day, when she answers, she cannot hear the customer and the customer cannot hear her. She hangs up, the customer calls back and it always work the second time. Usually no one has trouble doing outgoing calls.

Any Ideas how we could locate the problem with this?