Well then could someone check if this happens with the WP on their computers as well? What I'm thinking here is that maybe the problem isn't in the encoded videos but in the player settings, so maybe I could export in YUV after all and keep the file size down plus maybe cut back on rendering time of the MKV/BD video?
BTW, my MPC-HC won't play uncopressed AVI at all when I set it to Optimal Render Settings. What could be causing that?