Understood, thanks for providing that info. I dug up a DB23<->VGA cable I forgot I had and tried VGA input. It syncs at RGBHV, but it’s perfectly stable and works on every power-on. The downside is that video LPF doesn’t work with VGA RGBHV/RGBS, and I was previously using it to filter out some of the noise coming in. So as of now, it’s a small hit to the image clarity in exchange for hassle-free syncing. I think I can safely blame the noise on the Amiga hardware and not my settings. Here’s hoping someone eventually designs a digital RGB output for Amiga, as the video chip outputs digital RGB which is then converted to analog using an onboard circuit.