Originally Posted By: BIABman
It turns out the sound problem I was getting (related to this post) was that BIAB was transposing the song and playing back both the initial key (C) and Eb at the same time! The audio track was playing a conflicting key.

I am no expert but I believe once you generate your song and output to WAV files BIAB will by default save a file with the project name as a complete song with all tracks. Then, when you go to play the song again BIAB will automatically look for a WAV file with the project name and if it exists it will play it. So, when you changed keys and regenerated I suspect you didn't output WAV again so the complete song as a WAV in the old key was in your project folder and BIAB automatically played it.