First guess is you're trying to play a sound file recorded at 22k or maybe even 11k. KHP expects to see a 44k (CD quality) sample when you feed it an audio file.
You can resample a file into 44k usually by loading it into Sound Recorder, picking File/Properties, and picking "Convert Now." But the typical three minute track will become about 50 MB easily and you might not have the RAM to do this, since Sound Recorder works exclusively from RAM. Other audio editors can do this without such an impact on RAM, however.
I discovered a really cool audio editor called GoldWave
http://www.goldwave.com/ that can do what you want, and do a lot of other processing before feeding it to KHP. I think MTU has some tools for this too.