We have a RingCentral Polycom VVX series VOIP phone behind a Cisco ASA 5506 that will provision, work for about five minutes, go off-line for 20 minutes then reconnect and continue to work unless powered down. The problem can be duplicated and happens at multiple sites with the same configuration.
A review of the packet capture shows that the system disconnects when there are a series of duplicate ACK followed by duplicate retransmissions. After about 20 minutes a RST is sent and all is well.
This is the filtered capture from power on until reset -- phone is at 192.168.254.106 and RingCentral server is at 188.8.131.52. Any thoughts on problem and solution?