I have a Yamaha receiver that is switched on and off via a power switch. This means its most of the time off the grid. That is no problem as long as HA is running, but when i restart it says it cant connect to it (obviously) but then doesnt even setup the entity. If i then turn it on, it wont get recognized until i restart again. I dont know if this is a bug or simply isnt implemented but i think it should be. Maybe retrying the connection every 5 minutes or so, i dont know how the component works exactly. But it should always show up, if it cant be reached, just display it as off or unknown or so 