Yamaha CS80

are all 3 fuses intact?   ---- On Thu, 17 Jul 2014 11:14:08 -0500 bob@blzproductions.com [yamahacs80]<yamahacs80@yahoogroups.com> wrote ----        Hi Just servicing a CS50, and it's constantly outputting a whine of about 4120Hz.Unit came to me a bit battered as the PSU had shaken loose and trashed a few things inside.PSU PCB had become cracked, so replaced that with a working one purchased from Synthparts.Recapped the new PCB before I fitted it.I've done the usual, changed the logic on the KAS board and the S/H board, replaced power decoupling caps throughout etc.The only difference is that originally it took a minute or so to manifest... now it manifests immediately.I can see the signal on all power lines.Any thoughts?B