I had this happen recently! I was totally "squicked" out -- I LOVE that word.
I returned a gentleman's call about something he wanted to donate. We're chatting, I'm getting info, telling him how we handle possible donations, and the next thing I know... "FLUSH...GURGLEGURGLETOILETNOISES...GRUNT..GRUNT....Water running..."
During this whole thing, he kept talking to me, despite the occassional grunting.
I didn't take lunch that day. I guess I should thank him for helping me with my diet, but YEESH. UGH. No donation is THAT important, trust me.