Clients sending but not receiving during sync

Hello, I’ve been trying to narrow down what may be going with a sync issue between two clients, Mac and Windows. The symptom is that if a change is made on either side, the server will receive the change right away, however the other client won’t detect the change. This doesn’t happen on every file or location, but is consistent in that when a file/location is affected it stays that way and won’t ever sync again.

Things I’ve tried:

  1. Force full sync
  2. Reinstall the client
  3. Upgrade from 3.7.4 to 3.8
  4. Enable/disable virtual files
  5. Disconnect the server account and re-add it
  6. Restarts

There is no error in the log file that I can see.

Would really appreciate some additional ideas on what to look at to help narrow this down.