Audio Question (AIWA Mini System)

[telstar1]

I've got an Aiwa Mini System. It's the Aiwa CX-NAJ70 aka the NSX-AJ70.
The remote is a number of buttons that serve two purposes ... you shift the the alternat purpose by pressing the "shift" button on the remote.
All of the buttons have a label for the secondary effect except for one.

So obviously, I'm trying to figure out what that one button does when shifted.
When I press that one, and switch between the options, the display shows the following:

VF
AVF
MPX-L
A-MPX
VF-OFF

I can't figure out what the heck it means, and the manual, though it does make a nice attempt at explaining how to work the power button in every language known to man, doesn't say word one about what those akronyms mean.

Anybody with a better background in audio know what this does? It seems to change the audio but I'd like to know more.

Thanks,
Telstar

 

[telstar1]

bump

 

[Gunbuster]

Altavista translation of a russian site:

During the use of signal " KARAOKE CHD " you can carry out a function Of " multiplekh " - the separation of the source of musical tracking and microphone signal along the different channels the selection of data of regimes/conditions is accomplished with the aid of the knob/button " karaoke ": > VF (isolation/liberation of voice) > A -VF (automatic isolation/liberation of voice upon the start of microphone) > MPX- L (separation of signals " vocal channel - leftist") > A -MPX - the automatic separation of signals upon the start of the microphone > OF VF-off (switched off) under the effect of system " MPX- L " you can change distribution after harvesting knob/button " KARAOKE ". In this case will fluoresce " MPX- R ". under the effect of function " A -VF " or " A -MPX " you can change the rate of processes with the aid of the knob/button " karaoke ": FAST- quick action? " SLOSH " - retarded? " KARAOKE"- programming (str.2ya) you can program the reproduction of source- tracking. In this case the program can include to 15 songs

 

[telstar1]

Ah ... the thing mentions it supports Karaoke. I guess this isolates the audio for that purpose.
Thanks!