Is anyone else having any problems playing back videos? I stuck the PB on my MacbookAir (2013?) , obviously under Yosemite / Mavericks it was playing video files through VLC and/or Quicktime fine. But in El Capitan its dropping frames like anything, super choppy video, but the audio is always fine. Not massive videos, mostly DVD rips i've made, but none of them at even 720p. Any ideas?