If you encounter trouble with audio in the VR-headsets, it is usually fault in the hardware, included here are two guides for the HTC VIVE, and the Oculus Rift / Rift s.

HTC VIVE

Oculus Rift

1. Launch SteamVR from your desktop, Start menu, or taskbar.
2. Click the dropdown arrow next to SteamVR
3. Click Settings
4. Click Audio
5. Click the dropdown arrow in the When SteamVR is active, set playback device to field.
6. Click Headphones (Rift Audio).
7. Click the dropdown arrow next to the When SteamVR is exited, set playback device to field.
8. Click your standard speakers you use when not in VR

That's all there is to it. Now you won't have to go in and manually change your Rift's headphones to the default device anytime you use SteamVR to play games on your Rift.