Bang & Olufsen Beosound A5 Portable Wireless Speaker (Nordic Weave) - Manual (Page 17)

MICROPHONE
Beosound A5 has built-in microphones that are used by
RoomSense for optimising the sound of the speaker to its
placement.
If you wish to disconnect the microphones, move the
slider switch [ ] next to the charging port to the leftmost
position (switch will show orange). RoomSense can’t be
set up when the microphones are disconnected.
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