Hi @Jeremy_Moute, are you streaming online? Have you tried using a 5GHz network? I think it’s blocky or non-HD because the streaming quality has been adjusted to lower speed.
Also, can you please follow this post and double-check that the picture quality tweak is already activated for you (i.e. the sliders should already be in the correct position).
(At large screen size, from a close distance it is normal to see the ‘grid’ of pixels at 1920 x 1080 resolution. But it won’t be visible from normal viewing distance.)