Solved
Is STM32H7Rxx/7Sxx affected by OTG_HS "transmit FIFO corrupted" erratum?
Other chips have the erratum "Transmit data FIFO is corrupted when a write sequence to the FIFO is interrupted with accesses to certain OTG_HS registers" (eg ES0392 2.25.2 for STM32H743).
It isn't listed in the ES0596 rev5 errata for STM32H7Rxx/7Sxx - are those devices unaffected, or it just hasn't been listed there? Thanks.