I agree with Noel ... probably your MIDI synth in BiaB is not set up correctly.
RealDrums and RealTracks (green) are effectively audio, so your audio setup is OK. Yellow tracks are MIDI and need a functioning MIDI-synth to play. Probably yours is not functioning.

Pages 8 and 9 of the manual, and/ortry the MIDI bit from here: Band-in-a-Box® for Windows - No Sound / Driver Setup

Check or get that working before anything else.

The default synth is CoyoteWT, which doesn't have great sounds. There's a better synth mentioned on page 9 of the manual, but it's a bit fiddlier to set up. It uses .sf2 sound fonts and there are some pretty good ones on the 'Net. "Compifont", "Timbres of Heaven" and "Jjazzlab soundfont" are all good in different ways. I'd get CoyoteWT working first, before trying anything clever.

Jazz relative beginner, starting at a much older age than was helpful.
AVL:MXE Linux; Windows 11
BIAB2025 Audiophile, a bunch of other software.
Kawai MP6, Ui24R, Focusrite Saffire Pro40 and Scarletts
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