Later my impression about the S6000 spoiled when I discovered that the noise floor of the DA-converters (on all 16 outputs) of my machine is actually remarkably higher than should be expected from such an upper class sampler. It is connected to a mackie 1604 mixer. I tested for noice by pulling the volume of the headphones to a high level. Result: at 0 db fader position (middle position with no preamlifier input gain) noise floor is clearly rised and lies therefore above the mixer. Of course, by using many outputs the noise floor is even higher and reaches a point (e.g. 6 stereo outputs) where you cannot use the s6000 for professional productions. I have other gear: S2000 and Nord lead II. Both of them have much lower noise floor at the output. When setting digitally the output to -12 dB (S6000 system setup), the signal-to-noise ratio is simply too low for my taste.

Does anyone have experience with such problems? Is it normal or should I let it to be repaired?

Maybe there is something wrong with the power supply (not clean enough) ...