BBrain BQ06A-0550900-M Manuel D'utilisation page 10

The tumblers are locked in place during normal operation and unlocked using
the USB tumbler. The USB tumbler has 3 positions - closed, unlocked and open.
To customise the control panel, it needs to be in the unlocked position.
This tumbler also works as the way to enter the setup menu, for which it should
be fully open. This is only likely to be used in this way during setup, and will only
be used in normal operation for inserting USB sticks.
unlocked
Next
Back
fully open
Louder
Quieter
Next Louder
Back Quieter
fully open
unlocked
side view
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