Here's some steps to try:
- Is your volume in-app turned up all the way? Try checking in your System menu and ensure your sliders are up all the way.
- Do you have the correct output device selected? Check in Windows Playback Devices. You can find this by right-clicking the speaker icon in the bottom right of the screen and selecting Playback Devices. Ensure you have the correct device selected.
- Are the drivers for your Audio Device updated? RealTek HD Audio devices are particularly notorious for having issues if the drivers aren't totally up to date. If you're on a custom-built desktop computer, check with your motherboard manufacturer for the latest drivers. If you are on a prebuilt desktop computer or a laptop, check with your computer manufacturer for updated drivers.
- Is your system volume turned up?
Some audio drivers (such as ASIO4ALL) can stop VRChat from being able to access your audio devices. These drivers are typically installed with audio management programs like FL Studio, Ableton, Voicemeter, Nahimic, etc.
Please make sure to use Realtek or a similar direct audio driver that doesn't require exclusive use of your audio devices. If you use audio production software, please make sure it is closed while running VRChat.
If you can still hear world sounds but not any voices, please try installing the following file (Microsoft Visual C++ 2019 Redist): https://aka.ms/vs/16/release/vc_redist.x64.exe