Akai S1100 Tuning Noise

Hi,

Today i've noticed a problem in my akai s1100. It plays the original sample with no problem but when i play other notes (or applying even a 0.001 detuning) i hear an electrical noise. I checked the outputs & cables and they work properly. I don't think the problem is the sampling level or input connections bcs i'm having the same problem with the default waveforms inside s1100.

Here you could download 10 seconds sinewave example:
http://www.sendspace.com/file/lrsm52

I'd be really happy if you could help.

Thanks.