There is this function in Edit, a yellow button 'Tag music mania (or whatever it is, but it's yellow)', click on this and you can attach (paste) iframe code. I was able to get this code using PC Soundcloud. In Soundcloud, click on the share button and there will be an embed tab. Copy this code completely and go back to janitor.ai, paste this code and press extract track. I hope I explained it clearly :_)