Hardware 60 GB PS1 BC vs. Slim PS1 BC

[BasedKiliK]

I've noticed that when playing some of my PS1 games on my slim 120 GB PS3, they sometimes get sound and graphical errors, though the PSN versions for some of them fix those issues. Since the original 60 GB PS3 units contained PS2 hardware for backwards compatibility, will the issues described on the slim with PS1 games still exists on these consoles?