Hahaha...I totally understand what you mean. It drives me absolutely nutty when I have to use the washroom and some lady is in there doing her makeup and having a chat on her cell phone when I'm trying to poop!!
What I do is put a whole bunch of toilet paper in the toilet before I poop and then when the poop hits it doesn't make any noise because it hits the toilet paper and not the water. LOL It works all the time for me.