I'm sure this has been asked a 1000 times but Xbox party chat isn't working on the 2 xboxs in my home, this problem occured around November last year. Microsoft went through EVERY troubleshooting which made no difference. They told me to speak to ISP to open ports or something which Virgin did and made no difference and I eventually gave up and here we are over 1 year on and I want to play online again as does my son. We can play online but cannot access game chat or party chat. It shows connected by mic as icon shows on screen but friends can't hear me and their voice comes through TV. My daughter has a PS4 and no problems at all with party or game chat. Microsoft have no idea what's going on and neither do virgin as they say everything fine with my router. It was absolutely fine with no problems whatsoever until November last year. Any help appreciated.
Sorry to hear you're having issues with your Xbox one party chat. Can I ask is there an error message that pops up when trying to open or join a chat? Can you join games online and if so can you chat in-game?
Have your controllers got the latest updates? to make sure you go into setting>kinect and devices> select the controller then the 3 dots (...) then select the firmware which will be at the top and update?