Ok so I solved this annoying & strange problem and now feel stupid for not seeing it before.
My capture device takes it`s audio from hdmi connection to ps4, however for some reason when I connect my turtle beach px11 to the ps4 controller to get sound through headphones, so the sound from tv speakers does not interfere with my blue yeti mic, the sound then goes only to the headphones and gets cut from hdmi, therefore leaving my recording or live stream with no audio from the game.
I tried endless settings, optical cables, the lot, then after many wasted hours what turned out to be the solution came to me, simply plug the headset into the 3.5mm headphone jack at the back of the tv !
The sound still gets through hdmi to my capture device and sound goes straight to headphones and no sound comes from tv so does not interfere with my blue yeti mic.
Also as a bonus instead of plugging the usb power connector into the ps4 to power it, if I plug it into my pc I also get the audio from there, so essentially picking up two audio feeds through 1 headset.