sudden issues with sync

[realmx2]

I am having sudden issues with sync

• A device will get the error message: "Error while syncing. Unable to read remote data. Maybe you enabled encryption and your password does not match...?"
• I click "Ok"
• It then pops up another messsage "unable to load data from remote. Do you want to overwrite the remote data...."
• I click "OK"
• Now that machine will work, but the other machine, or the android phone will not work, and I get the same messages on them.

This only just started happening. I've been using dropbox without the encryption on. I've tried again with turning off compression and same error, I also tried by syncing to a local folder that all the devices have access to and got the same errors and scenario. So it seems like something has changed with the syncing logic.

All devices are on version 11.1.3