No game audio after joining party

This sounds crazy but I may have found a fix? While playing I joined a party n had no audio in the party or game. I turned off my xbox. Turned it back on, joined the party first n then loaded up the game. Woohoo! GAME AUDIO RESTORED! I know it sounds dodgy
but try it n let us know if it works. Hope it helps everyone!

I can send an audio voice message using the new headset on his console and also hear one that's been sent to him .And also hear game audio , but when you join a party or create a party or game chat there is nothing?

Hi. My name is Brilliant and I am happy to assist you today.

You can try troubleshoot audio issues in parties by the following:
Check the Xbox status.
Not hearing the other person after joining the party.
Getting echo when another person talks.
Not recognized by Kinect when you talk.
Party chat audio comes out of TV when headset is connected.
Game or app audio becomes inaudible during voice chat.

For more details on the above kindly visit: https://support.xbox.com/help/hardware-network/display-sound/troubleshoot-xbox-one-party-audio

I hope the above helps resolve your issues.

If you join a party with him just click the include audio button

Well if he's streaming on twitch you need to be in a party with your friend. Once you are... open up the party where it shows who's in the party and etc.. there should be an option where it says "Include my audio" Click it and your audio should be joined in with the stream.