Problem Pioneer DDJ-SZ noise is heard when I touch the buttons of autoloop

Good Nights,

I Have acquired the Pioneer DDJ-SZ 3 months ago and it works correctly except that on having recorded my session, a noise is heard when I touch the buttons of autoloop, pads, etc. That I can do to solve this?? I use the traktor pro 2 and only this noise appears on having recorded the session.

Thank you