Wonder if the old camera just didn't pick up the audio well enough. I have the game fully working now and it does it, plus on the YT I think I heard it later in the video. talking about a reset and Kings targets that reset on boot because they are driven by a lamp driver and a message about adding a resistor to under playfield transistors to avoid this. While doing some reaearch on this I found: While I hadn't heard about that with system 1 machines I don't imagine the design flaw that causes it to happen was corrected then.
System 80 machines sometimes have a power on thunk where a coil or coils fire.