Sony SRS-BTS50 - Manual (Page 61)

2. Hold the (call) button and slide the POWER/HOLD switch to POWER
ON/OFF until the power indicator lights up in green.
Note
Communication may become unstable in the “Priority on sound quality” mode,
depending on the combination of the setting of your BLUETOOTH device and
the ambient conditions in the area where you are using your system. Reset the
system to the “Priority on stable connection” mode by performing steps 1 and 2,
above.
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