Why is my Control dial malfunctioning?

Hi everyone!

Since a short while I discovered a problem: my E-510's control dial (not the mode dial) changes values when barely touching (and not rotating!). This makes photographing very difficult. I have not used it in very moist or dusty circumstances, so that could not be the problem, could it? What might be worth mentioning: it clicks normally when rotating. Full reset didn't work.

Does anyone have any experience with this?

E-mailing Olympus does result in a 130EUR research costs plus additional repair costs, which is more than the current worth.

Thanks!