Auto-importing from LW to iTunes is only an option for Mac OSX with LW version 4. However I think LW introduced the option for windows users with version 5 beta. (for both mac & windows users, to use LW 5 beta, you need a 64-bit machine. Java 1.6 is 64-bit & older macs & older windows computers cannot use this java version.)
Issues you should know about iTunes & iPod (click on blue link)
It's my guess those files are fakes.
Try playing those audio files with an alternate player, I recommend ToolPlayer;
Alternate Audio players (click on blue link). It's very small but a very capable player able to play many, many more audio formats than iTunes can.
Otherwise, try disabling then re-enabling iTunes importing option in LW's preferences. Sometimes it needs to be reset.