HDRI Backdrop is blurry

Hi there,
I am having issues with a blurry hdri backdrop. I imported an HDR and set it up as cubemap for the hdri backdrop. Its says: Imported: 6080x3040 - Displayed 4096x2048x6 (Cubemap) - Max In-Game: 2048x2048x6 (Cubemap).
So the resolution is already downscaled and I have enabled the “No Mipmaps” option. It is still blurry and I can’t get it sharp. Can anybody help me with this? I am not making any progress to fix it…

Best regards
HDRI Backdrop

Screenshot

HDRI Settings

Well, to make HDRI Backdrop more better you can set “Maximum Texture Size” to 4096 and then in Level of Details change “Mip Gen Settings” to NoMipmaps.