I own two Cats, both of which have suffered from tuning instability. On the
first it was a matter of thoroughly cleaning the j-wires and contact bus
bars as well as replacing the keyboard bushings. On the second I found that
resoldering the 2 ceramic caps that hang from the bottom of the board helped
with tuning stability...go figure! They occasionally wander a bit
especially in the first half hour or so, but since the repairs, they've been
pretty solid.
first it was a matter of thoroughly cleaning the j-wires and contact bus
bars as well as replacing the keyboard bushings. On the second I found that
resoldering the 2 ceramic caps that hang from the bottom of the board helped
with tuning stability...go figure! They occasionally wander a bit
especially in the first half hour or so, but since the repairs, they've been
pretty solid.