Sidechain doesn't work

I wonder if anyone has encountered this weird annoying bug in Resolve (I'm using v17 in Windows 10).

What happens is: if I try to activate sidechain in Fairlight to lower the music track automatically whenever there's a voiceover, sometimes (specially in a project with many sequences) it won't do that, but instead it will just show "Bus 2" instead of "Sidechain" in the "Bus outputs" section. The steps I follow are:

1) I open the voiceover track's dynamics section and click on "Send".
2) I open the music track's dynamics, turn on the Compressor and click on "Listen".

At that point, the configuration should look like in the capture below (click on it to see the relevant part):

DaVinci Resolve by Blackmagic Design - 17.4.6 07_11_2022 23_18_43.png (22.44 KiB) Viewed 1251 times

But instead, what I get is "Bus 2" instead of "Sidechain" in the "Bus outputs" section:

DaVinci Resolve by Blackmagic Design - 17.4.6 07_11_2022 23_19_10.png (18.85 KiB) Viewed 1251 times

And if I play the piece, the music is "ducked" the entire time, not only when there's a voiceover.

Sometimes, if I quit Resolve, restart it and configure the sidechain again, it works, but lately it has stopped even doing that.

Searching around, I found a couple of instances of other people with the same problem, but no real solutions. What's going on? Is it a bug?

Is the described behaviour with the Dynamics Processor's sidechain only present in Flexi Bus Projects?

Potentially isolated to Resolve 17.4.6 on Windows as not reproducing this behaviour with Resolve 17.4.6 or 18.0.4 on macOS.

FlexBus? I don't know, because I haven't tried opening any old projects. I should also say that this doesn't happen all the time, only in projects with many sequences.

Also, an even odder thing: when I quit and reopen Resolve, the timeline I had open has the sidechain correctly enabled... but if I switch to another timeline, then the sidechain disappears in the new timeline, and also in the previous timeline if I open it again.

Resolve 17.4.6, build 4.

What do you mean by "many sequences"? Lots of audio clips, lots of tracks..?
I just started to use sidechain compressing in my recent project (17.4.6 / FlexBus / Win10) without issues.

Around 20 sequences (which is more than what I have in most projects), and around 3-4 audio tracks in each at most.

I found a workaround in the end: go into Fairlight, disable the "Send" button in the voiceover track and delete the "Bus 2" flag, then quit Resolve. Reopen and then, using the "+" button, add a Bus Output. You'll get the option to add a "Bus 2" or a Sidechain. But it's quite annoying having to do this in each sequence where it doesn't work.

Ok, can't confirm this issue on my end. Way more clips and around 20 tracks.

Just experienced this exact thing. Very puzzling. Had to restart resolve and fiddle around with the send/listen buttons in the dynamics window to get it to work proberly.

Just here to stay that this issue still persists! And man, is it annoying!

Is this with Resolve 18.6.6? Note that Resolve 19 changes the Sidechain implementation.