Reading your problem, a similar issue to that I was experiencing, I am glad to inform I have two ways of solving this somewhat irksome issue.
Firstly, you can always Re-Record your audio using the "Wiretap" application (note not the "pro" version). Once recorded via playback of the original audio, it converts said audio into an "aiff" format, able to playback through "Quicktime".
Obviously this can be time consuming and will require further conversion into other formats if so desired. However I have found that subsequent updates of iTunes and legal issues have encouraged Apple to tighten their software to the extent that it's no longer easy to remove our "voice" recordings. Try viewing the following link for software to enable you, the user to regain control of your iPod;
http://www.engadget.com/2004/11/02/how-to-get-music-off-your-ipod/
This provides software for both PC and Mac and provides full "how to" instructions.
Happy recording.
