Its probably being a bit audacious but apparently you can import mp3 tracks into audacity and save them as midi files. But can you then import it into BBM
Audio to midi conversion works best with single instrument audio files. It is, after all, pitch to midi conversion. Having drums in a track really messes with things as drums are “unpitched,” but clearly play at some collection of pitches. Pitch to midi can’t differentiate a guitar from a piano, or a sax from a trumpet. But, if you get good midi out of a pitch to midi conversion, it can be used in the BB. The BB plays midi files on a single channel of midi.
Ableton also does a good job with audio to midi conversion, but it has the same issues. You can usually get a decent idea of the bass part, and instruments that are up higher than the drums (strings?) But, from an mp3 all that midrange stuff is going to get mixed together.
I have used the iZotop RX 8 music rebalance tool to first isolate tracks, save the percussion or bass track to mp3, then bring it into Ableton, and as Phil noted, Live does a good Job with audio to midi conversion. By creating isolated tracks first, it’s a much cleaner way of getting the beats or bass you want minus any midrange bleed. Use EZ Drummer or a midi Bass plugin for additional tweaking. Note, this is a time consuming process due to the processing in RX 8. I believe there are other apps to create isolated tracks. I find both the Isolated Bass and Drum tracks are 95 + percent accurate when converted in Live. Worth a try to see if it’s worth it.
I use Audacity quite a bit to add additional instruments to drum sets.