I'm using BIAB 2021, and I don't normally swap out drumsets from the default styles, however I'm trying to do that now, and it will not allow me to change the drumset at all. I can't even change from the variations within the existing groove. I can swap the drums, I can change the a or b style, but every time I regenerate the song, it's the exact same groove as before.

I have the latest update (4/26/21) installed, but I don't know if it's related to that or if it's been doing that for a long time.

I can change out the song style completely, and then I get new drums, but then I can't change those drums either. What am I missing??

It also won't allow me to disable the multidrum that's built into the style. It's the "_burning.sty" that I'm looking at, not that it matters. It seems to be doing this with every style. Can change styles, but nothing about the drums inside the styles. I can swap out any track except for the drums. Those I cannot modify in any way, shape, or form.

Well that is exactly what I am hearing also. Same original drums play not matter what you try to replace them with. I can only assume there is a simple explanation.

Presumably, the drum track is not frozen?

Correct. No tracks are frozen.

Confirmed. I definitely had the same (incorrect) results with _BURNING style. The drum track name in the mixer changed, but after a regeneration, the original drum track kept playing.

Have you tried it with any other styles? I randomly grabbed a few different styles and had the same result with all of them. I could change the style as a whole, and I could change any other track, but the drum track would not change for any of them.

Side note: I also could not turn off the multidrum feature either. I'd go in, hit "default" - which would clear out all the setting - then hit "ok," but it would not turn off. And when you reopen it, the original settings were still there and on. Its like it's not saving any changes being made to the drums.

I tried several others including _CANADA, _BYANDBY, _PRONTO and the drums changed OK.
Could you name some of the other styles that didn't change?

At any rate, this has been reported to the developers.

Right, that’s a specific issue where if a style is hard coded to use multi drums, the real drums can’t be changed. That would be a rare case, but we will try to fix that.

I am also experiencing a number of F-5 issues too along with being unable to change the groove "go from side stick to snare with ride" etc. Style change also doesn't work. I hope there are plans for another patch. This is a bit disheartening, when these thing worked before.