Honestly if I were them I would not make pros, preamps, are easy I would still make dacs and stereo preamps.. but for the processor I would have a company like Denon make circuitry and throw it in there chassis...
Specialize in amps{ht and music}, subs, music systems, and interconnects for it all... I wouldn't mess with speakers {people are too picky, and should be}, I would make passive and active subs {who can mess that up, lol}, and specialize in really nice music systems which they already have a good start, xsp1, xda2, and the usp1 and their cd player.... just maybe add a decent turntable that is a better value than the project carbon.... I think they would also be smart to jump on the class t small low powered stuff, maybe a little tripath that makes 40x2 for $80....