Advice for fanless 4k/x265 capable Kodi box

I’m looking for a new Kodi box for the bedroom.

Requirements:

  1. Silent
  2. HDMI-CEC
  3. Linux (Ubuntu) or Windows. No Android crap.
  4. Flash / SSD
  5. Capable of playing 4K in HEVC/H265
  6. Small

I have no clue where to begin. I would prefer to buy a barebone or something I just have to add a disk to.