duinsel, you are an absolute lifesaver! I was dreading trying to get my PX-160 fixed or having to replace it, but nervous to take it apart and potentially make it worse. Well, I dreaded so long that my warranty ran out and I figured "Might as well." Perfect! I couldn't believe it when my key (F4, for what it's worth) played beautifully. I almost cried. Thank you!!!!