Hi ST-2,
I've never heard of this issue before. Actually, there was a post on GTPlanet's main page talking about the spectacular frame rates in GT5P (rarely going below 60 FPS). But there are a few things that could be happening:
- Have you checked if the PS3 is overheating? If you PS3 is placed in a tight spot with no "breathing room", this could be a problem.
- Is there an specific place in the track where it happens?