Been seeing this exact issue since building mine about 9 months ago. More often than not the machine boots to a black screen. Pressing a button gets past the black screen (plays the startup sound and displays the wheel). I tried switching to Windows Media Player, same results. I then assumed it was one video in particular, of about 30 I have in the startup folder. I painstakingly removed all videos but one and rebooted, repeating with each video. It became obvious no specific video was to blame.
I've got a Geekom mini PC with an i3-8109U processor in it. Windows 11. I have Bigbox set as the default Windows shell. Virtually nothing else is installed on the machine (whatever comes with Windows with most of that disabled), Chrome, LB/BB, emulators. That's it.
Frustrating, but I guess I'll just remove the startup videos. Not the worst workaround, but the videos were a nice touch.