In photoshop CC if the last thing I clicked was a layer in the layers palette, the shortcuts on my keyboard won't work until I click somewhere on the art board. This has happened for quite awhile and I believe I had the issue off an on when using CS6. But now it is a constant issue even after restarting.
It's as if Photoshop thinks I'm trying to access something in the layers palette with the keyboard shortcuts and since that is not an option it gives me the alert noise that that function isn't possible.
It is VERY frustrating as I use shortcuts ( "P" for pen tool, "V" for move tool, etc.) constantly while working and have to make sure I click the artboard all the time first.