Yamaha SR-B20A User Manual page 63

TROUBLESHOOTING > When a problem occurs: Audio
The volume decreases when the sound bar is turned on
l The Automatic Volume Adjustment function is activated.
To prevent unexpected excessive loudness, if the sound bar was turned off with the volume set high, the
volume is automatically adjusted the next time the sound bar is turned on. Turn up the volume if
necessary.
– "Basic control during playback" (p.29)
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