Thanks for trying it out and the feedback! Spy Hunter and Bump N Jump were what I immediately thought of when I saw the cartridge and felt I had to go in that direction. There should be sound and music. Maybe 'M' got pressed and muted the sound? When I get home I'll check to make sure I didn't accidentally upload some version without audio. Or possibly I uploaded a version that defaults with Mute on. That seems like something I'd do.