Problem with rain

So, I tried google and search, quess I had wrong keywords or nobody has had this problem. However I've had this problem for years and even with different computers:

In changing conditions, the rain starts but the road wont get wet until the rain stops. After the rain stops, road gets gradually wet. So it seems, that for some reason the rain effects come when it's not raining and sun is shining when it's supposed to be raining. Kinda breaks the immersion. In the full dry race, everything is ok. Have anyone else had this? Any solutions?

I haven't played GP4 in a while but I do remember this, I'll check again. Not aware of a solution, hopefully someone else has one.

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Tahitian GP Circuit
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Easter Island Circuit
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