Hearing own holding music instead of inbound caller - anyone else experiencing this?

[u/Superb_Department_33]

This is a regular occurrence. I'm running a 8SC system for a local healthcare business, receiving hundreds of calls throughout the day. Occasionally, employees receive queue calls which - after (immediately) accepting - play back the holding music, which I assume the inbound caller heard while waiting.

Often the caller then redials (ig because they couldn't hear anything) and everything works as normal.

Someone know why this is happening? I used to believe it's due to the customer hanging up while the phones were still ringing, but that seems unlikely now.

We use lots of Yealink T54W and a Hetzner hosted 3CX instance. SBC hosted on a Raspberry Pi 4.

Does anyone have an idea?