Sennheiser AMBEO Max Instruction Manual page 52

Maintaining the AMBEO Soundbar | Max
52 | AMBEO Soundbar | Max
▷
Press the SETUP button for 5 seconds.
The display shows "Updating" and the status LED pulses yellow.
The Soundbar restarts several times during the update. The process
can take up to 8 minutes.
Hold
5s