Hi there,
I have a Yamaha CP30 electr(on)ic piano that I really like. I don't know if you can call it a synth though. It is a piano but it is pure electronic, in contrast with famous electric pianos like the Fender Rhodes. But it has a great "piano-touch", it looks great, it was cheap and if you plug it in an electric guitar amplifier it sounds nice, especcially when using phaser pedals etc. I can make it sound a bit like a Fender Rhodes, but then at a fraction of the cost!
A sustain pedal is essential for that kind of sound and here is my problem/question:
when I push my sustain pedal I get a high-pitched sound, one note, something like an overpowered signal or an electric guitar that is in overdrive. On my guitars I like that, but with my piano I don't.
Does anybody recognize this and know what is the problem here and more important: what can I do about it?

thanks in advance!
Marcel, Amsterdam