You should install youtube app from playstore and in HQ settings you'll not see 4k option even on 4k videos.
You should also install AIDA64 app from play store, it will show you detailed specs of this tv.
One more thing I noticed, they advertised this TV with 12GB DDR3 ram, it is even mentioned on their website but in reality it has only 1.5GB ram.
The day I bought this tv it start crashing randomly. I registered a complaint and their rep visited my home next day, he changed power supply, since then it's working fine.
Can you tell me how much IPS Glow you notice on Gray/White and Black screens?