Unfortunately, some Mac & PC users are experiencing an issue casting our streams to Chromecast devices. 

We are working on resolving this issue.

In the meantime, to cast your Chrome tab follow these instructions:

Start the video from your My Library page. 
Click the 3 dots in the top right corner of Chrome
Click 'Cast'
Select your Chromecast device from the pop-up menu.
Once casting starts click the Fullscreen button on the video player

Or, you can cast from Android or iOS using the nugs app - or connect your Mac or PC to your TV via HDMI. 

Be sure to power down your PC first, or restart after connecting. Connecting HDMI to your TV while your PC is on may cause audio/video sync issues.