I have some of these:



The one my desktop PC is connected to shows that red switch flickering, like it has a neon or something inside it.

Another one is on and devices are all powered fine, but the red switch is not illuminated at all, it is dark and cycling the switch has no effect, it remains unilluminated.

Is there anything to this? the one that has flicker, is that a fault? could it cause noise or something on the power coming out?

Perhaps the flicker is just a neon and the other strip where it's always unlit has a broken neon...

Does the red flickering mean anything? The reason this caught my eye is that the PC crashes about once every 24 - 48 hours and always gives a different cause (I've extensively investigated this and know a lot about PCs and can't pin it down, a full memory test revealed no issues) so it crossed my mind just now that there might be a fault in that power strip that somehow occasionally upset the power to the PC (the PC is actually plugged into a UPS and the UPS into the power strip).

Might the flickering "neon" be generating spurious noise that upsets the PCs PSU?

FYI I tested the PC by bypassing the UPS a few days back suspecting a faulty UPS but it still showed the same crash behavior so I ruled out the UPS as a cause.

Just to be clear too, the flickering is incessant and irregular, not some constant looking flicker frequency.

 

Another one is on and devices are all powered fine, but the red switch is not illuminated at all, it is dark and cycling the switch has no effect, it remains unilluminated.

Sounds like the neon bulb us burned out. It happens. I have a device under my monitor that controls 5 different outlets with a master switch. 4 of the bulbs are burned out. One flickers, and the other is mostly off...

 

My experience with "surge suppressor plug strips, and other plug strips, has been that the illuminated switch is often, but not always, a neon bulb illuminated device, produced as cheaply as possible. The neon indicator MUST HAVE A CURRENT LIMITING RESISTOR, and the tolerance of the resistor value is very broad. An entertaining experiment is to shine a light on the flickering indicator, which in many cases will cause it to glow steadily. To verify that the flickering is not caused by low mains voltage will require an AC voltmeter.
SOME "surge suppressor plug strips include an indicator LED to either show that the protection is still active, or to warn that it has failed. Those are quite different.