DDJ 400 No RCA Output

Has anyone had issues with this since the recent firmware update? I can play master output fine through my laptop soundcard but absolutely nothing is coming out of the RCA port. Have tried all the usual troubleshooting stuff. Tried various different cables, even into an external soundcard so you can tell from green/red clip lights if there is a signal, and there definitely isnt a signal. Made sure Rekordbox is completely up to date and tried various USB cables to connect to laptop. 

Just to reiterate, master output is fine from laptop but seems that RCA output on the controller is dead. 

Any help would be well appreciated!