Hey there Pingu,
I’m sorry we weren’t able to get to you sooner, but I have been taking a look into this for you. Ultimately Overwatch is only able to access the Audio Channels that Windows makes available and this would generally mean that there is another application or setting on your PC that is blocking all the available devices from being used in-game.
A couple of recent Windows Updates have worked on some sound issues and the hotfixes Microsoft implemented may have effected how your specific setup now works:
August 30, 2019
Addresses an issue that prevents certain games from leveraging Spatial Audio capabilities.
September 10, 2019
Symptom
Microsoft has received reports that audio in certain games is quieter or different than expected after installing this update. At the request of some of our audio partners, we implemented a compatibility change that enabled certain games to query support and render multi-channel audio. Due to customer feedback, we are reverting this change as some games and some devices are not rendering multi-channel audio as expected. This may result in games sounding different than customers are used to and may have missing channels.
Workaround
To mitigate the issue, open settings in the impacted game and disable multi-channel audio, if this option is available. You can also search in the Windows Control Panel for third-party audio device control panels and disable Multi-channel audio or Virtual Surround Sound, if these options are available.
We are working on a resolution and estimate a solution will be available in late September.
I don’t know is this is related in any way to the issues you’re describing, but the timing seems like it may fit.
In any case, in situations like this, the first thing that I would advise is to work through the Troubleshooting Sound Issues guide, including the Advanced Troubleshooting. I know you’ve already tried several steps but I want to ensure all relevant suggestions from this have been tried.
Following this, please check for any updates to your Astro A40 software, and if that doesn’t help, please try reinstalling the tools to see if that changes anything with your options in Overwatch.
If you still have troubles after trying the above, please can you collect System Files from your PC, and then upload them to a file-sharing platform (such as Microsoft OneDrive, Google Drive, Dropbox, or Pastebin etc.) and then share the link with us.
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