I can record cassettes to my MP3 using the line-in recording. I can play the recordings on my MP3. I can find the files on my computer. They don't specify a file type, they are just called "file." When I copy the files to CD, I get a message on the CD player there is no audio. Is there a way to change the file ext so they will copy as music files? Is there another way to transfer MP3 recordings to CD? Ultimately, I want to be able to play the music that is now on cassette in the CD player in my car. I read a similar thread about burning CDs but it talked about audacity and I'm not familiar with that, I'm trying to use MP3. Thank you.