Identify the Unmarked LED on MSI H170 Gaming M3

[Ghosts83]

I'm having trouble IDing an LED light just above and to the left of the front IO connections on my MSI H170 Gaming M3 motherboard. This LED is sitting just above the slow-mode boot switch and will either hold steady or flicker while the pc is running.

 

[BadActor]

The only two references I see in the the motherboard manual refer to the debug LED and a power LED.