Home button no longer works 5.1 factory

I flashed 5.1 and it's kind of OK (although a few app stopped errors happen) but the home button only works from the task switcher screen. It doesn't work from any app. Tried with Launcher, tried with Nova Launcher. Also, setting Home in Nova Launcher to an app doesn't launch that app. Something eats my home clicks. But what? I do not use a custom keyboard.