Bigbean

my copy of outrun does something very similar where the only sound that plays, if anything, is the vocal samples that are replaced with random static-y noise, and that's cause (in my case) there's a ground fault on the ROM chip itself that unfortunately isn't fixable

i assume you don't have access to a different model of mega drive to test it on? i ask cause for my copy of outrun, it boots with no sound on my model 1s, it doesn't boot at all on my model 2s, but on my model 3 it runs and sounds fine