OverlapBox missing detection when too many calls

i duplicated the scene 30 times and suddenly the robot arm no longer detect what is passing by, this happens half the time.
overlapsphere used to be rock solid in 4.6, with 100s of calls per frame
did they introduce a boxcast budget? i didnt see a field in the physics tab

If it works in earlier Unity versions but stops working in 2019.3, then you probably found a regression. Perhaps caused by the PhysX upgrade in 2019.3.

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