Hi @xsky_fall I'm sorry to hear that you are experiencing issues with your audio in Assassin's Creed Valhalla.
Can you please go to the audio settings on your Xbox and change the audio output to 'Stereo' if it currently set to something else such as 5.1 or 7.1. After you have done this go back into the game and check if you are able to hear Eivor's sounds.
If the issue persist can you please provide an image of your Xbox audio settings, in game audio settings and your TV audio settings.
Can you also confirm if you are using your TV speakers for your audio output or if you have speakers or sound bar.