Okay, this one has me thoroughly stumped.
I think I've found three pieces. Am I right? Two of them look very similar to each other. I just don't understand how I'm supposed to be interpreting the data being given to me.
"Imagine how they sound" -- they sound choppy, they sound squeaky, they sound BAD. None of the hints are helping me.
One of the things that frustrates me so much about some of these puzzles is that they assume certain experiences by the puzzle-solver. So many of these puzzles seem completely obvious in retrospect after we've solved them -- it's because they ARE obvious to anyone who's tried the technique. Case in point: puzzle 17, where you had to "mind your plusses" (for the URI escaping). I already knew how URIs are escaped before going into the puzzle, so I had absolutely no problems with the plus/space bit of the problem; however, I saw lots of messages by people who were rather confused at why their decompression was failing.