Audio and Movie Maker?

Simply put, the program is not lying to you in what it's saying. For whatever reason, certain files just may not be compatible with the program you're trying to use, or they may in fact, be corrupt. Try to download a different copy of the same songs your having problems with and see if it makes any difference. If it persists you may have to adjust the configuration or settings of the program as that might be the root of the problem. If all else fails, try uninstalling the program, restart the computer and then reinstall it. A fresh program install will eliminate many variables.