oil pressure fine but light comes on above 2000 rpms on 1995 Audi 90 Quattro

as i said i changed the oil and filter . ran car for about 20 miles parked it light did not come on the whole time. Then noticed oil leak at oil pressure switch for the light was leaking pretty good. So I want down to autozone put the one they gave me in now light and buzzer go off again above 2000 rpms. Oil pressure at normal temp is 2.5 bar and goes up with rpm. Maybe wrong switch? The one I took out is original equipment. says 1.6-2.0 bar on it. Maybe something in oil screen at oil pick up? I don't know because I have good oil pressure.

Thank You
Matt 95 Audi Quattro 90

Asked by for the 1995 Audi 90 Quattro
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