Sorry to hear that, but I'll need some more information to help you further...
- What controller is it?
- What version firmware is installed on the controller?
- What version of rekordbox are you using?
- What is the operating system you're using?
- What driver version is installed for that controller?
- What is the bit depth / sample rate of tha WAV file?
- Did you recently import that WAV or was it analysed with an earlier version of rekordbox?
- Have you ever moved or renamed that particular file?
- Does it happen with more than just that one song?