Biab uses Sforzando to play the instrument samples.
If I edit one of these sfz files like 61 Classic Bass.sfz in a text editor
and change 61 Classic Bass.wav to 61 Classic Bass.mp3 or 61 Classic Bass.ogg compressed formats they still work perfect in Biab app or any DAW.
I can convert the RealTracks to ogg or mp3 and create a sfz to play back any section of any RT file instantly playing from one section to another section in another file using the keyboard notes.
Biab relies purely on decompressing wma/m4a (when wav/aiff not present), writing it to RAM then rendering to wav/aiff, that was needed way back in the past. You need to make a quantum catch up leap.
Krystal Audio Engine(2004) plays back compressed ogg files direct.

Sforzando can play WAV, AIFF, FLAC, OGG or MP3 they could even make it play wma.
Again this is another reason why the BBPlugin can play wma/m4a direct.
2023 a year to see, to finally break free, liberty.