My mother also owns a Wiim Amp Ultra. She inadvertently let the remote control battery go down to zero. She fully charged the remote, but it was still not working.
It seems the remote will become unpaired from the unit if its battery goes down to zero. Trying to pair them up using the app does not work when this happens. This is what you must do if this happens:
1. Restart the Wiim Amp Ultra using the app.
2. Then pair the remote to the WAU using the app.
A restart of the WAU seems necessary before attempting to pair. I hope this helps!
It seems the remote will become unpaired from the unit if its battery goes down to zero. Trying to pair them up using the app does not work when this happens. This is what you must do if this happens:
1. Restart the Wiim Amp Ultra using the app.
2. Then pair the remote to the WAU using the app.
A restart of the WAU seems necessary before attempting to pair. I hope this helps!