CDJ 850-K Sound Delay when using CD's or USB

Hello, one of my CDJ's has started having an sound delay issue. For e.g when I press cue or play on a track I have about a 3-5 second delay until I get any sound. I have delay on every button,  from Jog wheel, Vinyl mode, to selecting next track. I have this on CD's and USB. I have used the same media in the other CDJ 850 K that I have any it works fine. I have changed the power and the leads just in case it was that but still I am not getting anything. If anyone could help me that would be amazing.

Many thanks

Dom