Chat/Headset audio issues - Alpha Insider Skip Ahead

Fill out a detailed report, giving make and model of headset you use and send it to the development team.

I am in Alpha Skip ahead and sometimes get these issues. You could try backing out of the Insider program, to a public build and seeing if things work.

Remember Alpha and Alpha Skip Ahead are the cutting edge OS builds and can be full of bugs.

Well if he's in the insider programn then he got a update today had the same issue the alpha & apha skip ahead builds are broken for 50% of the people that are ih that group so don't update your console if you're in alpha or alpha skip ahead

If your console is in the Insider Preview (Alpha or Alpha Skip ahead) try to disconnect all controllers and headsets, and only connect one controller and one headset.

Also read here: https://news.xbox.com/en-us/2018/07/11/new-preview-alpha-1810-update-7-11-18/

You must be invited to become an Alpha Insider or Alpha Skip Ahead Insider, to do so You must Very active in Xbox, doing missions and report the bugs You see in the system, as much as You do this, so You Will be Very close to become an Alpha Insider. You
must be at least in Delta preview to become an Alpha Insider, but You Just need to be an Insider to be invited to become an Alpha Skip Ahead, but this one is very rare to be invited and there is a certain number of people to be invited, no more than that,
If You were not invited to be Alpha Skip Ahead certain time, so You must wait a Second chance when they Will invite New members.

"xbox not being able to play dolby atmos"

According to the Latest Alpha skip ahead Insider release notes this is still an issue the engineers are tracking and working on.