David, that's a good problem statement now. I really don't know the answer, and BIAB 2009 is so long ago that I don't remember what the menu options would have been. I think I know this stuff pretty well and I'm older than you, but I have limitations!

So, my suggestion is to contact PG Music Support. They may even have an older working version of BIAB, but especially, they can remote into your machine and try to find the problem.

Be sure to post the solution once it's known, so we can all help others.

I first thought the solution lies with your external speakers or mixer - whatever you are using - since the headphone jack works. It doesn't seem like it could be a BIAB problem, and yet you say everything else works...

BIAB 2009 had some early RealTracks and RealDrums. Could you give us one more possible clue: is the sound of MIDI and RealTracks equally low, or is one affected more than another?

BIAB 2025 Win Audiophile. Software: Studio One 7 Pro, Swam horns, Acoustica-7, Notion 6, Song Master Pro, Win 11 Home. Hardware: Intel i9, 32 Gb; Roland Integra-7, Presonus 192 & Faderport 8, Royer 121, Adam Sub8 & Neumann 120 monitors.