I got a terrible bug on the PS1 when beginning a brand new ff8 game and first time encountering an enemy.
No matter where the fight is (training region in the college or open world), the enemies are visible, they are even moving (idle animation is playing) and Nobou Uematsus music is playing.

Just no Squall is appearing!! I can't do anything and have to restart the PS and try again, but no change.

My brother already played the whole game some years ago with the exact same cd's and machine. Now me wanted playing too.

Somebody knows what I'm talking about?
How could I avoid this thing from happening?

Is there a scratch or mark on the disc that's causing it to crash? Try cleaning the disc with a dry cloth. Failing that, it could be your console that's malfunctioning and may need repairs.

Other than that, I have no idea what the problem could be.