Quoted from Skins:Maybe I'm misunderstanding you guys but I believe it "flickers" to let know know "the wizard of oz" has be completed (spelled out) and its ready to award a bonus. I'm sure that is why it flickers...or a hell of a coincidence on my machine, lol.
No, that's a pretty obvious and slow pulsing on and off. The flickering referenced here is a hyper-speed flashing/dimming due to inconsistency in 12V voltage that only an LED has the instantaneous response time to show, and that appears to be exasperated by pretty much everything else that exists on the 12V rail.
While the 12V rail is idling the issue is most obvious on the OZ head (and not necessarily all the time), but motors and other items operating can be seen by more predictable dimming and flickering in the topper and, to a lesser degree, the spotlights. This has been discussed and confirmed for some time in the WOZ group, but with that said JJP has gone through a number of different power supply designs/combinations, so some might be worse than others.
It's also entirely possible that you and others are physically incapable of seeing minor examples of the flickering - and that's a good thing. Back in the CRT days I was unduly affected by monitor refresh rates, to the point that the standard 60Hz that most everyone used would give me instant headaches. Even 75Hz wasn't good enough. My computers always had to be capable of running at a minimum of 100Hz for me to be comfortable, so it's likely I'm just more inclined to notice and be irritated by such flickering in WOZ.