Welcome to the forum. There are a few ways to do transposition in BIAB.

If Noel is correct, and he always is, then the explanation is that the key IS saved with the song but it can be OPENED BACK UP in another key IF you have visual transposition on.

You can also see if a visual transposition is in effect by looking at the normally empty little area to the right of the displayed key signature, between that and the tempo.

Trust me, I've been confused. That's why I asked for the VISUAL indication a transposition was in effect, and they added it. For my trumpet it will say +2 [because a trumpet sounds two half-steps lower than concert pitch when reading the same pitch]

I play various instruments pitched in C, D, Eb, F, G, A, and Bb. Generally, to be safe, I save songs using different file names where I add the transposition to the end of the file name. Example: AmericaF.MGU or AmericaBb.MGU

If that is not it, do the Factory Settings he described. If it still fails, list for us the steps you are taking. I know a few other things to check.

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.