[sdiy] noise source crap out

[Magus Ship]

"All of a sudden" my homebuilt noise source, which is based on the
Electronotes and ASM-1 designs has crapped out.  What used to be a rich hiss
has become a futzy stream of what sounds like badly band pass filtered pink
noise.  Around this time the ground connection at my power supply became
desoldered (unrelated? related?).  My question is whether the transistor or
the filter caps to get pink and Random Low Frequency outputs would be the
problem.  Is it possible that a transistor that provides good noise can
change or crap out over time?  Or is it more likely that a cap or a bad
connection in the filters would produce this effect?
thanks as always.
Gavin