Yamaha CS80

Hi everyone,

I have owned my CS-80 for about 5 years now.  It spent 3 years of it's 
life in a repair shop in Michigan (Soul Fruit Electronics), and was 
supposedly completely fixed but is not.  He did fix most of the problems 
- replaced all of the CMOS chips, rebuilt the power supply, got all 8 
voices working, all of the presets and user presets working, and both 
outputs work.  I can't endure another multi year ordeal to get the rest 
of the problems worked out, so I am wondering if there are other good 
techs close to Detroit, MI.

The problems are: 

1.  The top voice sine wave works, but the saw and square waves don't 
make any sound when engaged. 
2.  The chorus and tremelo engage, the volume drops, but they don't 
affect the sound as a tremelo and chorus should.  Everything just sounds 
quieter.

Does anyone have any recommendations for how to fix these, or any 
recommendations for a reputable tech that is close?

Much appreciated,

Dan