Absolutely love Chromecast. Today I discovered Chromecast will turn on my TV and correct HDMI input port when I start casting. Very nice!
But why didn't Google build in some form of "OFF" function? That idle backdrop slideshow feature is annoying as the TV makes me look every time the picture changes. At least let me turn off the slideshow feature.
However I found a workaround. I solved this by creating a Google+ album with two un-captioned black pictures in it.
By customizing the backdrop to only show personalized photos in this new album I get rid of the annoying picture changing and show a near black screen with only some faint gray text at the bottom. Only the cock (that can't be turned off) changes on this dim screen. Almost perfect.
Not sure what feature in this TV causes itself to switch off but after a certain amount of time, the TV knows the picture has not changed enough and the TV switches itself off. Probably some burn-in protection.
It is a cludge workaround for a feature that should be painfully simple.
Chromecast should allow backdrop to be turned off and after a timeout it should simply send a switch TV off signal via HDMI and then turn off the HDMI output until a request to cast is received again.
Maybe it is an American thing to leave the TV on 24x7.