We all know that white amps go wilder.
I got this beautiful Peavey T-Max (used) for cheap. Between the demonstration at the seller's place and set-up in my attic, it managed to lose all capability to sound decent (producing only farty, quiet, creaky noises). Some basic trouble shooting revealed that the problem was with the pre amp, most likely the tube channel. The golden tip came from a Dutch bass players' forum: after removing the tube (to fully by-pass the tube preamp channel) the amp came back to life and started to sound rather good in solid state mode. And... bonus... after reinstalling the tube, the tube channel also started working again.
First impression (paired with two Hevos Super 12 cabinets): nice, creamy sound; beast of an amp!