Have to "Test" audio devices before audio starts playing

Question

I recently got a new headset for my PC (an Astro A40 w/ a mixamp.). It connects to the PC via USB and optical. It is exposed to Windows as 2 playback devices Astro MixAmp Pro Game for game and Astro MixAmp Pro Voice and one recording device Astro MixAmp Pro Voice. All 3 devices show as a USB audio devices in device properties:

For audio output the Astro Game audio device is set to my default device, and the Astro Voice audio device is set to my default communications device. For recording the Astro Voice is set as my default device.

Everything works correctly except whenever I turn my PC on, I have to start some audio playing, open the sound device manager and "Test" the Realtek Digital Output device to start audio playing through the headset (it sometimes takes several attempts):

I imagine this is caused by the device being detected as a USB device but the actual audio comes via optical out.

I've tried finding what the issue is but had no luck as any combination of search terms containing "test", "audio" and "windows" comes up with dozens of generic "How to Fix Sound Problems in Windows 10" articles.

Any ideas what I need to do to get audio working on PC startup rather than having to test my audio first?

Answer 1

As it turns out, both the setup insert provided in the headset box and the associated setup YouTube video failed to mention relevant setup steps for users who intend to use the optical port on their machine rather than having both audio and mic. work via USB.

The missing steps are provided here (emphasis mine):

If your computer features an optical output, locate the digital optical output and set this as your default device. Right click the device and navigate to Properties > Supported formats. Ensure that Dolby Digital Live is enabled and DTS is disabled, if featured, and that the sampling frequency is set at 48.0 kHz.

Once I performed these steps the headset is now correctly output to first try after booting the PC.