Noise question.

[alparent]

I'm not to sure how to ask this question?
I'm building a switch box using Arduino, and I want to use stereo jacks so I can detect what inputs are used.
I was thinking of using them like we do to switch effects (when you plug in the jack its shorts the connections to ground)

So I could detect if me pins are HIGH or LOW. LOW would mean the the input is connected.
I was wondering if doing this would add clock noise or any other noise to my signal?
I don't think so........but what do I know?