I had this a lot in first two months after my op. It was to do with food getting stuck at the wrap and the pipe gets blocked. The stomach convulses - I picture like a snake would if that makes sense - to try swallow and clear the blockage and I'd have those squaks for maybe 20 mins. They are a bit like hiccups, but not, very loud, disconcerting and embarrassing. Little sips of wAter helped me. I imagine that as each wrap is different each timetable is different. Hopefully as the wrap settles and swelling reduces this will go. Is there a check up due? Eventually you'll want to.check the wrap just isnt too tight, but too early yet.
Hope that helped