DTC P0523 - anyone see this before?

I was at the track on Sunday and while going down it the SES light & chime went of during each run.

I checked the DTC and I had a PO523 code. Which is a Engine Oil Pressure Switch - High Voltage.

Now we changed the oil pump a few weeks ago to a high volume melling and it runs about 65 pounds at WOT. Wonder if this is causing it - the chime scared the crap out of me on the first run.

Anyone seen this before?

The car is an 04 GTO a4
baby cam & Dart heads

there is an oil pressure switch that is known to fail. your oil pump is good. but the measuring switch is faulty. it's located behind the intake manifold. on the block, right hand side. just replace it.