Matrix Element X - Led turns red

[Alessandro_3126]

Good morning, 
I have an Element X since almost 1 year now. 
For the first time, this morning I found the power led red. 
When I turned on the device, the led changed to a sort of purple. 
I turned off the unit and did a power cycle, after that the Led was back to normal and showing the usual white light. 

Could you tell me the meaning of the red led ? I could not find any explanation on the manual. 
thanks 
Ale