i just double checked it again. try running sonic-cd (or any other fastscrolling game) in pal 50 and pal 60. in pal50 its just like on a megacd, the scrolling is not skipping (shaking)!
and i noticed that while in the bonus stage (after collecting 50 rings in a level) after a few seconds the SFX just disappear. the music keeps playing though, and in the next level the sfx wont come back.
sorry for all these "complaints", just wanted to let u know.