Hi @Anonymous User,
Given that you've now confirmed the make and model of your TV and that it should be capable of supporting 1080p, it would seem that you've found an HDMI related bug 😉
It may also be worth pointing out to people in general that as all the NOW TV branded boxes output video at a fixed frequency of 50Hz, if you access content from services such as YouTube, that has been encoded at a different frequency, the motion will not be fluid. This is not a bug.
And for anyone else reporting such issues... It is vital that you all confirm the make and model of your display devices in your posts!
Cheers all