Need opinions

Ok so this is kinda gross but my fiancé refuses to see a doctor & both me & his old roommate have heard him in the bathroom & something seriously isn’t right. Literally every time he goes #2, his butt explodes & he makes huge gas/diarrhea noises. I’ve seen the aftermath after & the toilet bowl sprayed with brown. It’s really starting to gross me out especially now that I’m pregnant & all day sickness has hit. Any idea what could be causing him to go like this? It can’t be normal. Something gastrointestinal has to be going on. I remember the 1st time I heard him (was only our 2nd date) & my mouth dropped. I had to cover my mouth to keep from laughing at the sounds 💨💨💨💨💨💨💨💨💨💨💨💨💨💨💨💨💣🧨💣🧨💣🧨💣🧨💣🧨💣🧨💣🧨 I’m worried though too what’s wrong & now wondering if this is something our child will inherit. The sounds ya’ll!!! Like nothing I’ve ever heard. He eats normal food too. Nothing out the ordinary.