Error Message: QQ_Put with RFLinkSyncQueue

Received a call about session drops from a customer. Event log show the below error message. Any ideas what this means?

Error message:
QQ_Put with RFLinkSyncQueue has failed. Caller: 0x03105bc8, MsgType: 0x000000ff, ExtType: 0x00000037

Received another call about this - anyone else seen this or can Cambium chime in on what it might be?

QQ_Put with RFLinkSyncQueue has failed. Caller: 0x0336a018, MsgType: 0x000000ff, ExtType: 0x00000037