Philips 328E 4k monitor flickering while connected to M1 Mini

I am sure that it is not the first complaint but I feel very sad, that almost nothing changed after 10.3 Big Sur update. Philips 328E 31.5" 4k UHD (non HDR) display is flickering while connected to M1 Mac Mini. It doesn't matter if HDMI or USB-C to DP is used. Before update, the flickering could be reduced by "degrading" display port form 1.2 to 1.1 in monitor settings menu. Now there is no difference between both. Flickering is triggered by certain colors - that's why changing monitor color profile or monitor gamma seemed to be helpful. Doing anything to avoid displaying those certain "triggering colors" helps. Strangest thing is that mere presence of the "triggering color" on screen doesn't trigger the flickering. Problem causing color must fill a certain area of screen or window containing the color must be moved to certain position on the screen. Full screen of the "triggering color" doesn't always start the flickering. So I am sure that flickering can occur with certain colors present on screen but it also depends of size and position of area they are filling. Flickering is not plain but there are vertical flickering scanlines. Is there a problem with color bit depth used by monitor (some kind of round-off error when monitor is trying to represent the problematic color)? Is monitor loosing Sync-on-Green signal (scanlines are interlaced with black)? ...needless to say the monitor is flawless connected to other computers :-(