Plug Inline Mute Cable into headset and Headset In/Out port on MixAmp Pro. 4. Turn on your PS4. The MixAmp Pro will turn on and the Power button will be red. 5. Go to Settings, then select Sound & Screen, then Audio Output Port. Under Primary Output Port select Digital Out, then Dolby Digital. Under Audio Format, select Bitstream (Dolby). 6.