This is the second time this has happened since I bought this TV a couple of months ago....

I have my Chromecast plugged into the HDMI3 port - last night I quickly flicked a YouTube video up from my phone (too lazy to go hunting for the video in the YouTube app on the TV) and when I had finished watching it, attempted to go back to the 'normal' TV channel (HDMI1 - being fed from a TiVo unit).

None of the buttons on the TV remote work - except for things like Menu and Volume. The Input Select buttons on the TiVo remote don't work either.

I turned the TV off overnight, but this morning, after rebooting it, the input is still HDMI3 and the buttons on the remotes are still unresponsive...

I don't recall what I did to fix it last time (I suspect some fortuitous button mashing combo did the trick)....

Any hints?