Yealink T46S Phones - Every Other Ring Works

[straight1]

Experiencing an odd issue at a remote location. We have an on-premise 3CX server running version 18. These remote phones (using a T46U SBC) have an odd problem where any incoming call (external or internal) causes the phone to ring such that the end user can only pick it up every other ring. During the "silence" between each ring, the phones screen goes back to the home screen. Essentially, the screen of the phone is flashing, during ringing it shows the incoming call, but during the small silence between rings it shows the home screen.

All phones are running the latest firmware and have been reprovisioned. I'm not sure what else to check.

 

[TheodorosG_3CX]

This sounds to me like the ringing is starting all over or there is a loop, did you ensured that?

 

[straight1]

This sounds to me like the ringing is starting all over or there is a loop, did you ensured that?

There are no loops. The network consists of a single switch and firewall.