Flashing objects

[BausChaus468]

wen every i move, fly, etc. i get my blocks glitching out by disappearing and green lines with blue lines coming onto my screen... sometimes its hard to tell if im even in a room, ive tried re-downloading it, getting it on a whole new user on my pc but it just keeps glitching with the blocks, this happens with every block. I would love if someone found an answer to this.