Audition Not Editing Original File

I'm used to working in Audition CS6. I import an MP3 and the sound waves are all uneven, like an MP3 naturally looks like. When I open the same MP3 in Audition CC 2014 the MP3 seems to have been converted to something else because the sound waves are all razor flat. I don't want that. I want to be editing an actual MP3 file. How do I set my CC 2014 to edit actual MP3s like my CS6? I don't want them automatically converted into something else before editing them.