Ok, this is a weird one.
My setup:
SFC 1-Chip + RGB Bypass mod
OSSC
RetroGamingCables SCART
Game: Ganbare! Daiku no Gen san
So basically what happens is that when I am playing I take the game character onto a blue background, and I stop moving around (there is nothing going on in the picture) – and all is good. The second I pause the game (the music stops playing but nothing else changes gamewise), wavy moving noise appears on the large blue area of the sky. The second I unpause the game (and audio starts playing), the noise disappears.
Any idea? Thanks!