Bubbles from bottom of tank fill tube
After the toilet tank is filled and the ball float is all the way up (fill level is fine and well below the bowl fill tube), I notice intermittent bubbles from the bottom of the tank fill tube that sits parallel to the flush valve. I believe that's what the item is called. It will happen for a few minutes off and on and then stop. I know there seems like a ton of air bubbles going around on that side of the tank as the water rushes in during the fill. Could that be the issue, the air coming back out? Or is it new flush valve time?
By the way this flush valve has three screws around the top of it to hold the top together and then two on the arm for the ball float. Not sure if that helps at all or not. It's an American Standard 4078 tank.