Sony MHC-GNZ444D Operating Instructions Manual page 69

You can also change the "KEY CONTROL"
2)
setting by pressing KEY CONTROL 
reduce the key and KEY CONTROL 
increase the key when the Karaoke Mode is
turned on.
The "KEY CONTROL" setting is
automatically changed to default setting
when you change the track or title.
Depending on the disc, you may not be able
to do the above operation.
The "VOCAL SELECT" setting is
3)
automatically changed to "OFF" when you
set "KARAOKE PON" to "ON. "
Depending on the disc, you may not be able
to change the vocal.
For DVD VIDEOs with one or no guide
4)
vocal recorded, you cannot change the vocal.
You can change the vocal when the audio
sound track is recorded in Dolby Digital
format.
When playing a DVD VIDEO, the function
5)
only works for Dolby Digital Karaoke format.
For DVD VIDEOs without guide melody,
you cannot hear the guide melody even if you
set the setting to "ON. "
The highest score is reset when the system is
6)
turned off.
If you press other buttons on the remote, the
score calculating function may be canceled.
In some cases, you may not be able to use the
scoring mode.
Note
Each Karaoke setting in the table above is
automatically changed to "OFF" or to the
default setting when you:
 turn off the system.
 change the function.
 connect the headphones.
 turn off the Karaoke Mode.
 open the disc tray.
 change the disc.

to

to

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