I wonder, Robin, if it was one of the "WAV compressed files". I've encountered some WAV files which were EXTREMELY small for the length of them. I found out there is a method for compressing them with MP3 compression but still naming them WAV and playing them as normal. I've not found the program which does this yet, but I have found these really small WAV files and they have the MP3 string near the beginning of the file.