Windows toolbar visible while in FS mode

When I run the AVS the windows toolbar is visible. It was working fine two days ago but something changed in the
settings and it pops up now. I tried changin the "keep taskbar on top of windows" but that was selected prior to the problem.

Ok, after some messin around and changing the resoution to 1280x800 @ 32bpp instead of 16bpp the taskbar goes away, but in the taskbar buttons on the right next to the clock, sometimes something blinks through and pops up strobing every couple of seconds 🧟 I am effin puzzled

AVS's resoltion doesn't have anything to do with the taskbar.

Rightclick on the taskbar, go to settings and disable "always on top" (or something alike; I have a Dutch version of windows)

That might solve it

It might be the result of a 3rd application running in the taskbar(i.e. not windows or AVS).