E2 Media Player Compatibility

Recently I'm finding more and more of the movies I'm downloading won't play on my Alien 2. It's either jerky, or the sound won't work, or it just won't play at all. It's like the codecs are all outdated or something like that. Is it just my box? Is there a work around?

Cheers

I'm using a My Cloud NAS, which are reckoned to be fast. My Alien has a wired connection to the router. It's a cable modem - around 120mb. Everything should be fast enough.

I get the impression this isn't the norm.

I changed the color setting to YUV in the audio visual settings and - viola - it works a treat.