I also had problem with the lead in volume, and eventually resolved the problem by using a lead-in type of 2 bars 'a' pattern, which is a drop down in the count-in / metronome option.

It works with RealDrums and may work with midi as well. Rather than the consistent 1-3,1234, it actually gives you a 2 bar feel for the rhythm as well as the tempo.

Some drums are louder than others so be careful which pattern you choose


BIAB for Windows Version 2019 (643)
Windows 10 (1909)