I have now gained new insights into the VSync problem, because it seems that the TV or the HDMI detection is really to blame. I just had my Raspberry Pi connected to my 13-year-old Panasonic 3D TV and the VSync option works exactly as it should. What I also noticed is that the screen modes are swapped in the video setup menu, which you can select when selecting a game before starting Amiberry via Retropie. On my old TV, the 50 Hz modes are first in the list and only then do the 60 Hz entries follow. On my Philips TV from 2014, it is the exact opposite, so that I have to set the correct mode every time I change TVs. However, it does not seem to take the 50 Hz modes into account at all or does not switch despite the selection and only runs at 60 Hz instead of 50 Hz, which I find very strange, because the TV is definitely capable of handling both refresh rates. This also works with all other emulators, whether with VICE (C64) or all RetroArch cores such as NES, SNES, Mega Drive, Arcade, etc. Just not with Amiberry, which I find very unfortunate. The Retropie team would probably have to release an update to detect the connected screen in the Amiga Setup Menu. I actually thought that HDMI screens were all standardized by now and the only explanation I can think of is that it has something to do with an error in the setup script for Amiga core.