built a 3x3 piston door at my base entrance and it works fine when im there but when i come back from a mining trip half the pistons are extended and the door is just stuck open. java survival, single player. did i build it wrong or is this a known thing
chunk borders. bet your door is sitting across two chunks
yeah press F3+G to see chunk borders, if the line goes through the door thats your problem. when one chunk unloads before the other the redstone gets cut mid update and stuff breaks