Originally posted by NalsrA:

My spatial audio was already off.
However, I found a fix that worked for me. I just had to close Sonic Studio and then the audio started working after relaunching the game.

Really strange because all my other games have no audio issues, just Valheim.

Windows has this option per every audio device with "allow application exclusive access" or sth. along those lines. Try changing that option and running Valheim and Sonic Studio at the same time again? Maybe that will help.
And/or start Sonic Studio after Valheim?

Are any of the other games using the unity engine too?