what are your Sequence Settings.? i can duplicate the “pixilation” you are getting on my desktop by using NTSC DV as my frame size DV/DVCPRO as my Compressor. If i go to HDTV 1080i as my frame size and Apple ProRes422 as my Compressor it looks pristine…(well nothing looks pristine on the desktop..but on my broadcast monitor its beautiful).
Do you have a broadcast monitor as a reference?