Extender light suddenly red/orange at random times

My extendor's 2.5ghz icon is normally, or suppossedly green ( which obviously means its working perfectly fine at around 60 Mbps).  Then randomly i realize while im using my computer that the internet becomes much slower. The light turns red and cycles back and forth between red-orange and then stablizes to green I usualy get a stable 60-65 Mbps but when the light changes color to red or orange Mbps drops to 5-40. Why does this happen? This does not happen on my main router. I am using a wired connection from  my extender to pc. 

Thanks