Sounds like BIAB is doing exactly what it is designed to do. Give you the various strums/bars you would need to make the song the way you want it to be in a DAW or RealBand.

But, have you tried typing in a new/same chord at the beginning of each bar? Sometimes this has worked to make the same initial pattern play for each bar the chord is placed on.
If you have 8 bars and only have a chord at the beginning of that 8 bar section it's more likely to wander into the other random patterns.

Does the noise in your head bother me ?