Sony Bravia KDL 50EX645 showing black thumbnails for movies

My other media devices are displaying the correct thumbnails for my videos, however my Bravia seems to ignore the thumbnails and just pulls the first frame of every video, which happens to mostly just be a black frame.

Anyone know a way to fix this? I've looked through all my TV settings, but I can't find anything that would turn this off.

[Illico]

What is the format and name of your thumbnails files, and what are there locations ?
What are the settings on your serviio console (metadata) ?