Streaming setup help

I know this has been gone over millions of times i just cant figure it out
Xbox one > astro a40 tr's with mixamp in console mode > elgato hd 60 with no aux cord plugged into it*
Computer > elgato hd 60 > ice blue microphone > aux cord going from stream output from mixamp into the headphone jack ( obs wont start if there are no speakers hooked up )

All I want is my gamechat,party chat to be heard over my stream... now this is what I have done opened up astro command center and mess with all...

Streaming setup help