Yamaha YAS-107 Owner's Manual page 37

Audio
Problem
No sound.
No sound is coming from the
subwoofer.
The volume decreases when
the unit is turned on.
Cause
Another input source is selected.
The mute function is activated.
The volume is too low.
The power cable of the unit is not connected properly.
Input jacks on a playback device are connected.
Signals that the unit cannot play back are being input.
The unit is configured so that HDMI audio input signals
are output from the TV.
The HDMI control function is disabled.
Sound from an HDMI control-enabled TV is set for output
from the TV's built-in speakers.
The volume of the subwoofer is too low.
The playback source does not contain low-frequency
signals.
The automatic volume adjustment function is activated.
To prevent excessive loudness, the unit automatically
controls its volume within a certain level when the unit is
turned on.
Remedy
Select an appropriate input source (p. 25).
Cancel the mute function (p. 28).
Turn up the volume (p. 28).
Make sure that the power cable of the unit is connected to an AC
wall outlet securely (p. 24).
Connect the input jack on the unit and the output jack on the
playback device.
Change the digital audio output setting on the playback device to
PCM, Dolby Digital or DTS.
Configure the unit so that HDMI audio input signals are output
from the unit (p. 33)
When connecting a TV that supports ARC (Audio Return
Channel) to the unit using an HDMI cable only, enable the HDMI
control function (p. 33).
To output audio signals from this unit with the HDMI control
function disabled, connect the TV's audio output jack to this unit's
TV input jack (optical digital) via the optical digital audio cable (p.
22).
Use the TV's HDMI settings to set audio output to any option
other than the TV's built-in speakers.
Turn up the volume of the subwoofer (p. 28).
Play back a sound source containing low-frequency signals, and
confirm that the sound is output from the subwoofer.
Turn up the volume as required (p. 28).
37
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