lg 4k

I am trying to complete a triple 4K monitor setup with no luck. LG 27UD68-P monitor is in the center. Left and right are two LG 27UD69P-W. 27UD68-P +27UD69P-W This are the exact factory model numbers. The center monitor 27UD68-P is way brighter than the ones on the sides. Even the left and...