Dunno if it's the same with GRX, but I've been fiddling with an SLX derailleur that has an extra bit that sits against the hanger tab, and then the B screw sits against the extra bit. If your mech has it, double check it's sitting right.
@Bearlegged started
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Dunno if it's the same with GRX, but I've been fiddling with an SLX derailleur that has an extra bit that sits against the hanger tab, and then the B screw sits against the extra bit. If your mech has it, double check it's sitting right.