@marqs – Yes it does seem possibly related to brightness maybe, it happens with spells or explosions so it’s possible the screen could be going white or something. But it is SPECIFIC spots of all these games (same spot every time)
I do have 2.5MHz set – I have never touched Analog sync Vth or anything else on those screens (as I wasn’t sure what they did).
Could it be caused by something in my setup?
I have my consoles NES, SNES and PS1 RGB (all cables from retrogaming.uk) into a HAMA SCART switch, then that goes to a SCART audio breakout – then into a SCART to Component adapter and then component switch, which feeds into my OSSC.
I will try messing with the setting you mentioned, although I have no issues with sync in PS2, NES or SNES (in PS2 only if the game switches res during a menu or something)