Ship it to Krell!
I will tell you that they do absoloutely the best work out of any repair center that I have used. Your unit comes back, cleaner than it left, they internally clean the product, and they will not let the unit out until it sits on the burn rack for a lengthy time. They are fanatic about the cleanliness and care that they take with your unit.
They are not cheap, and I'm not a big fan of a few of the policies that they have. They will charge for $100+ for a new carton if you do not ship the unit in the original box, and they will insist on replacing expensive capacitors, at a hefty premium. But all of this, they feel is needed to keep you happy after the repair, and ensure that two months later you are not in a bind again. That is what you ultimately want anyhow?
I'm not too sure what the value is on a KST-100 these days, or if it is worth having repaired, but it probably is at least worth a call to Krell and shipping it to them for a repair estimate.
Try to get a 1980's higher end electronic product repaired, Marantz, Sony, Kenwood, etc. You will be hard pressed to find the transistors, capacitors,etc. Krell can still repair the first amps and pre-amps that they manufacturered.
It is all built into the price of the product.
If you really do not want to ship it in, call Skokie TV and electronic rapair in Wheeling, and see if they can help.