I don't know if that's the problem, but it could be a factor.However it usually results in a "buffer overrun" error. Try burning at a lower speed. Also some mp3's might play fine in a player ( winamp for example )but the encoding might not be good enough quality to burn. Some music files may be corrupt to begin with and these will never work. The illegal operation error makes me think there is a problem with the install of the program, or something else on the computer that is conflicting with it. Try uninstalling and then reinstalling the software. Also, before atempting a burn, make sure no other programs are running, disable virus protection, and select "copy to hard drive first" in the software.
If you're going through Hell...keep going... (Winston Churchill)
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