I am viscerally repulsed by public music playing in places where I can't reasonably escape. The absolute worst that I'm frequently stuck with is busking in NYC subway cars/stations. The music is usually terrible, although sometimes good, and on rare occasions great, but I don't think it should be allowed at all.

I don't have as much of a problem with street-corner busking, in large part because it can be avoided, but even that drives me nuts when I can't get away from it (outside a place I work, for example).

I love music, and when I'm in the mood, I'll seek out a street performance. City parks are great for this, and I think they're an appropriate venue. A rail car is not even remotely appropriate, and a subway station during your unavoidable morning commute, with loud brass instruments and a shitty PA system, echoing off the walls, ought to be a crime.