Hello world, I just recently found a d50 (813265) that has not been powered up for years and years. When I tried to power it up it was a horrific high pitched sound ( 6 kHz or thereabouts). I changed the battery and reloaded data from card. Still the same noise out ( it is incredibly hot signal). I am planning on cleaning the contacts with a good contact cleaner to see if that improves the buttons. Does anyone have any idea on what the noise output may be? Perhaps it'll need new caps? Does anyone know of any similar issues? I really love the sound of this and really would like to keep and preserve it. Cheers!