I have an M-Audio 61es. I was rearranging my studio and when I attempted to remove the 61es from the stand (On-Stage 2 tier stand) I noticed it was stuck. It took some force to remove it and when I did I saw that the keyboard seems to have melted where it was contacting the rubber protectors on the stand. The rubber was melted right into the bottom of the keyboard. Other than that it has worked fine. Anyone else encountered this before, or have any idea why it happened?