burning audio cd of mp3 files

[Craig White]

I have installed mpg321, xmms-mp3 and k3baudiomonkeyplugin but when I
try to add mp3 files to k3b, I get a message...unable to add the
following files due to unsupported format.

What's the trick?  Do I need to use a program other than k3b? Which
program?

Thanks

Craig