Nano was working perfectly until I had to reformat for windows computer. Now, it does not respond well to touch.

I recently purchased a ipod nano and briefly had it synced with my macbook pro. I recently sold my macbook pro and had to reformat ipod nano. Since then, the ipod nano does not respond very well to touch commands and sometimes goes into apps that I did not select. It is impossible to switch from page one to page two one app screen.

Thanks,

acdc1996