Razer Opus 2020 creates hiss

I just purchased a brand new unit of the Razer Opus 2020 ANC.
Model number: RZ04-02490101-R3M1

The ANC creates its own high frequency hiss, almost sounding like the ocean.
If I turn off ANC - it goes away, and when I turn it back on theres about 1-3 seconds of perfect noise cancellation before the ocean noise slowly crescendos back up and remains constant.

Is there a way to stop this? Is it a defect? Clearly the unit has the potential to create perfect ANC because it is capable for those short 1-3 seconds