By default, the mixer channel instrument assignment is determined by a .dk file loaded at startup.

Here are those default instrument assignments from the Options Menu.

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midi channels.png (168.04 KB, 126 downloads)

BIAB 2025:RB 2025, Latest builds: Dell Optiplex 7040 Desktop; Windows-10-64 bit, Intel Core i7-6700 3.4GHz CPU and 16 GB Ram Memory.