Bathroom Mufflers

Sometimes in the bathroom I can hear my family downstairs talking quietly. Then I realize that I just dropped a big loud stinky. I leave embarrassed wondering, is there a better way? I either need to learn to shit quietly or these air ducts need mufflers. I learned the longer you hold it in the louder it comes out! So, I need mufflers on my air ducts.(or my ass) But how? Lining the passage with insulation won't work. That would just restrict air flow and collect dust. So I'm thinking each (bathroom) vent needs an insulated flapper; smooth on the bottom, carpeted on the top. When the air flows, the flap lifts and the smooth underside lets the air breeze past. When the flap is down, the carpet captures your nasty sounds. You'll need to co-ordinate your shits with the end of a heating/cooling cycle but this could work. Besides I have a shy colon and can't crap while my mother- in-law discusses denture paste with grandma.