Sequential circuits samplers

periodically, it seems as if some voices are a bit softer/scratchier
than others...is this a sign that the voices are dying?

also, i have my prophet plugged into a furman power conditioner. 
because the on/off switch is in back, i leave it on and turn the
sampler on when i turn on the furman.  is there any reason to think
that this may harm the sampler in any way?

thanks for your input.
nader.