Sound shorting out on Clarinova CVP-207

Hey there! I have a beautiful 2001 Yamaha Clarinova CVP 207. I first encountered this piano when I lived in its former owners home, where it remained mostly on played except by his disabled son. I brought another roommate into the house that was very talented and would play it wonderfully for us for a couple years. After I moved out, at some point the piano started exhibiting a problem of being horribly shorted out, sounded like the speakers were blown very badly. Somehow, I took the piano from them when they wanted to give it away and between doing some flipping of switches on the input and output channels and doing a factory reset, the piano came back to perfectly functioning for about a year.

Eventually though, the piano started to have its problem again and it is very specific.

After the piano is played for a few minutes, sometimes less if many layers of sound or simultaneous notes are being played, The piano starts to short out and make a sound like the speaker is blown, especially the right side.

The issue does not seem to have anything actually to do with the speaker, the problem is exhibited at times if run through external speakers, though, the higher quality the amp that it’s put through, the less the deterioration comes.

At some point I think I’m going to have to take it apart myself because I don’t seem to be able to find a tech close to me who’s willing. (Grass Valley California, near Tahoe and Sacramento).

Any hope for me? I imagine I’m going to find one place where some circuit gets hot and shorts out and either replace it, trim a wire, or clean some corrosion. It doesn’t seem to be a software or speaker based issue. I don’t have experience doing this type of thing but I’m extremely smart and assembled computers when I was a teenager and feel competent with following instructions especially in videos. The actual disassembly and inspection seems intimidating tho hard to even figure out where to begin.

It was the nicest piano I’ve ever seen / heard, I hated leaving the house because I didn’t want to leave the piano, when they gave it to me later I was so excited and determined to fix it.

Thanks to anybody who read my thorough description!

(It also inherently has extremely heavy keys, like twice the weight of a normal upright, but I think they kind of get looser when used a bit, like the lube warms up from friction… But feedback about that stuff if you’re informed is good. This website seems to sell replacement keys at different weights…)

Oh and also note, when it had its problem in the first place before I took ownership, the sound would be garbled from the moment it was turned on, seemed surely like it was the speakers. Only now in its modern version of the problem does it have the warm up before shorting out issue.

Hello there
2 problems:
1- you need a new keyboard assembly. Do not try ANY lubricants to fix the hard key action issue.
Waste of time and it doesn’t work. Eventually the keys won’t go down at all or stick down. REPLACE whole assembly. About $500 from Yamaha parts dept.
2- Sound issue is a bad DM board (main board). NLA at Yamaha, sorry!
Time for a new piano…sorry dude.

Hey so somehow I already made significant progress on it by turning the speaker settings from speaker / headphones to just use speakers. The problem definitely has to do with that output wiring. Now after a couple of years being unplayable after a couple minutes, it is playable! But, has a little staticky shorting sound once or twice a minute, not as loud as before…