Reviews on Amazon's retail site indicate that this TV also has the "one audio click per second" issue with Dolby audio, at the higher end. I have the same issue, with the Panasonic 43" TV from John Lewis that What Hi-Fi advised was a great buy (particularly with Atmos, but also with straightforward BBC content from the 4K fire-stick).
I have to think that recommendations, and reviews, from What Hi-Fi, are not thorough.
Why doesn't What Hi-Fi dig in to this pervasive issue, of TVs with Amazon Prime, causing audio ticks once per second? The effect makes programs completely unwatchable.. It's amateur hour.
So far, my experience is that 4K just "doesn't work properly"..
I look to What Hi-Fi to stop being happy-clappy, and instead, to help victims to solve these issues.
I'm not a bit happy with What Hi-Fi. Mainly, I'd advise against buying a 4K TV, to use with Amazon's offerings..