Toshiba Smart TV "Video did not start playing in time" error

Hi, I have PMS running on Ubuntu 15.04, and a Toshiba Smart TV (40L3451DB) connected to my LAN via Ethernet. Plex app on the TV sees my libraries just fine and will play music, but won't play any videos. App version is 2.4.30, (Smart TV Alliance 2.0).

I can watch videos remotely on my laptop through the web interface, and I can watch them on my Android smartphone.

The TV app sees the same videos, all the metadata's there, but it won't play, it waits a while then gives the "did not start playing in time error).

Network connection to the TV says it's at about 13Mb/s, I've dropped the quality to 2Mb/s, still get the error, can't play any videos on the TV at all.

Any ideas?

I've attached the server log.

Thanks

Bransby