No audio when playing Oxygen Not Included
If you are able to run the game, but cannot hear any audio (even if sound levels are set in your game's options), here are a couple of troubleshooting steps that may be of help:

Update your audio drivers
Ensure is that your computer's audio drivers have been updated to the latest version.

If the issue persists:

1) Go into your Windows Audio Settings;
2) select "Change other sound settings"; 
3) Click on PLAYBACK tab and right-click your default audio playback setting and choose "Properties"
4) Click on the "Advanced" tab and on "Default Format", scroll down the list and set the value to 24-bit, 48000Hz.
5) Click on the "Apply" button to complete the change.

From there, launch the game once more and you should find that the audio is back in order.

NOTE: If you have any audio software such as Nahimic 3D Sound, try temporarily disabling or uninstalling it to see if that resolves the audio issue.