It's blue, it's bright, and it signifies sadness.
No it's not hypothermia but the 'Blue Light of Death' , which is said to be afflicting a number of new PlayStation 4 consoles.
Reports suggest that an unknown, but significant, number of PS4 units appear to be experiencing critical failures, indicated by the presence of the pulsing blue light.
The blue stand-by light - which appears after switching the console on - refuses to turn white, say those who reported the problem.
In a statement to CNET, a Sony spokesperson said: "We are aware that some people have reported issues with their PlayStation 4 systems in the US.
"We are closely monitoring for additional reports, but we think these are isolated incidents and represent a very small percentage of total units shipped to consumers to date."
Sony has issued a lengthy set of trouble-shooting tips but the best remedy appears to be the drastic step of sending your console back and hoping for a working one.
"After a two hour wait, a 10 minute phone conversation mostly involving address and ticket # exchange, Sony is sending me a box to ship... my DOA PS4 and they're going to ship me a brand new PS4 in return... The customer service rep I talked to was extremely reassuring, confident, and knowledgeable which was extremely nice... Also I should remind everyone with DOA's that the customer service rep on the other end is a person to who is not the cause of your problem... Well most of them aren't at least. There's always that 1%"
The PS4 launches in the UK on 29 November - here's hoping the issue is resolved by then.