@SoheeLee,
Welcome to the HP Support Community!
I reviewed your post and I understand that you are facing issues with the audio on the VR headset.
Don’t worry, I assure you I will try my best to get this sorted.
Some applications, including many of those launched through SteamVR, can lose audio or hang when the audio device changes as you start or stop the Mixed Reality Portal. Restart the app after you have opened the Mixed Reality Portal app to correct this.
When another multimedia USB device (such as a web cam) shares the same USB hub (either external or inside your PC) with the Windows Mixed Reality headset, in rare cases the headset's audio jack/headphones may either have a buzzing sound or no audio at all. You can fix this by plugging your headset into a USB port that does not share the same hub as the other device, or disconnect/disable your other USB multimedia device.
In very rare cases, the host PC's USB hub cannot provide enough power to the Windows Mixed Reality headset and you may notice a loud burst of noise from the headphones connected to the headset. If this occurs please file a Feedback Hub bug immediately. Workarounds that have helped some users include not using extension cables, using a dedicated, external powered USB 3.0 HUB or trying a different USB port on the PC.
Let me know how it goes and you have a great day!
If you wish to show appreciation for my efforts, mark my post as Accept as Solution. Your feedback counts!
Cheers!
The_Fossette
I am an HP Employee