Korg 01/W makes strange beep... LCD problem? Advice needed!

[Daniel Oberfeld]

Hi list!
My 01/W beeps! That is, not in the audio output but by himself,
immediately when I switch it on.
The tone seems to come from beneath the data-entry slider.
It's a high pitched one, maybe C#5 (should be 555Hz or something).
This is getting on my nerves when using it in my silent room..
My guess would be that this is produced by the LCD or the LCD-driver, I
somehow recall hearing about that. Seems the driver produces a high
frequent voltage for the illumination ?!?
I sent an email to Korg-USA service, the guy who replied confirmed that
the LCD-driver *might* be the cause of the problem.
Did anyone here have a similar problem, maybe on another synth?
I'd like to get more information before looking into this complex
beast..
Regards,
Daniel