Munchies:
My partner isn't a very gassy person, but he is lorge. About 410 last we checked. However, when he was actively gaining, I noticed they went from kinda quiet to deep and brassy. However, I think that's more to do with stomach size and less to do with fatness. When he stopped actively gaining and let his stomach shrink up, his burps got quieter
It must be fun. Afterwards I don't know if you like burps or not.