Its extremly fast that the eye cant even really catch it, the sound effect is the key to the transition so if you blink you can hear the transition.
There is a transition in season one but its nothing anyone can decipher, could be the living room infront of the couch or the set.
But all you really need to know that its mostly just ETC footage, non usable footage and since the transition is only a few frames and blured nobody can decipher what it is.