I'm using the latest core version (v240409) with the RetroTINK-4K and direct_video=1. Via the second page of the Status menu, it appears that the resolution changes from 2406x258 in 60Hz mode to 1895x258 in 75Hz mode. Because the auto-decimation setting doesn't change despite the reduced resolution, this causes bad cropping and pixel sampling not seen in the 60Hz mode.
I'm using the latest core version (v240409) with the RetroTINK-4K and
direct_video=1. Via the second page of the Status menu, it appears that the resolution changes from 2406x258 in 60Hz mode to 1895x258 in 75Hz mode. Because the auto-decimation setting doesn't change despite the reduced resolution, this causes bad cropping and pixel sampling not seen in the 60Hz mode.