When you place down two Redstone Dust on two floating blocks, a Redstone torch in front of one of the blocks and a block at it, the Redstone torch switches between unpowered and powered really fast for exactly two seconds. The rest of the time the Redstone Torch and the Redstone dust are both off. This repeats every 9-10 seconds. Also, the Redstone torch makes the same sound when the two seconds are over, as Lava makes when you pour water at it. It also starts when a block, that was touching the torch is destroyed or moved away by a piston that was touching it. I only tested the bug in 1.16.4 and 1.15.2