It's Sony again, the X700
This is the budget player so it has some esoteric features removed, mostly stuff a smart TV has anyway.
My A/V unit doesn't support 4K but Sony have a work round, plug the player directly into the TV and then add a second cable to the A/V for sound.
4K disk buyers beware! There is a lot of 'Ultra HD' in the shops that isn't 4K at all, it uses HD masters and upscales them to 4K which is what a 4K TV does anyway. Here's a cheat list:
Real or Fake 4K
YouTube has 4K demos such as
Wildlife in 4K