[sdiy] bit one

[Colin f]

> describe the problem a little better: something is modulating 
> everything.
> the oscillators sound almost like they're frewuency 
> modulated: on some notes
> you have a pure tone, on others you have what my mono-poly in 
> fm-mode sounds
> like.
> and the 'sound staying on after the eg has closed' is more 
> apparent when you
> open the filter. when full open there's only a slight drop in 
> volume if the
> key is released with the release at zero.

-snip-

Nasty interaction of parameters like that sounds like it could be a bad
4051 in there - with plenty crosstalk between demultiplexed CV lines
giving you the 'modulation' you don't want.
I'd pull any 4051's you can find, put in sockets for them (if they
aren't already socketed) and fit new ones.

Colin f