Crumar Musical Instruments User Group.

I've had my DS-1 for a month now and for the first 3 weeks it worked
great.  Now the sound goes in and out, almost like the VCA is being
controlled by the LFO but it's not the case. The sound will fade in
and out as opposed to just cutting.  Sometimes when it comes back in
the highest note is sounded and releases slowly, regardless of how the
ADSR is set.  It does this in all 3 outputs; high, low, and headphone.

Any ideas as to what may be the cause of my problem?

Also, this place is offering a paid download of the service manual. 
Anyone know if this is reputable, and/or worth the $35?

http://www.musicparts.com/products.asp?Company=Crumar

Thanks!

-Ollie