I just got a new gaming PC, and have been having problems with sound level for ESO (but *not* for any other application).

Initially, I just used the onboard Realtek sound device, and found that ESO sound is very low, even when the Windows volume mixer shows it at 100% I tried a fix recommended online, which is to change the sound driver from "Realtek High Definition Audio" to "High Definition Audio Device" (I think the latter is more generic and not Realtek-specific). This fixes the volume problem, but adds another problem, which is I occasionally get noticeable static/interference type sounds which tend to obscure the normal sound, which isn't surprising, really, since I swapped a Realtek-specific driver for a more generic one, so it just may not be 100% compatible with the Realtek sound device.

So I then decided that maybe I need a slottable sound device, and bought an ASUS Xonar AE sound card. It arrived yesterday and I just installed it now. It has exactly the same problem that the onboard Realtek sound device had! The ESO volume is very low, but all other applications on Windows have normal levels. With this sound card, I can't apply the above workaround that I applied to the Realtek device.

I also can't use the sound device Properties "Enhancements" tab, because this sound card doesn't have such a tab, so I can't use the "Loudness Equalization" option mentioned in some online discussions.

I've tried the fixes mentioned in this earlier thread, they don't work:
https://forums.elderscrollsonline.com/en/discussion/62703/sound-is-really-quiet-compared-to-other-software
Also tried this fix, didn't work:
https://gamefaqs.gamespot.com/boards/615805-the-elder-scrolls-v-skyrim/60983647
Also, the links to the Bethesda forums on both the above threads appear to be broken, I just get a "topic doesn't exist" error message.

Tried setting AUDIO_VOLUME="200.00000" in UserSettings.txt, it makes no difference (and this value may not even be reccognised by the software anyway).
Also tried running Repair on the game via Steam, no effect.

For now, I've plugged my PC speakers back into the port for the onboard Realtek sound device, so I can play ESO today (otherwise the sound is so low I can barely hear it)

Any ideas on how I could fix this, anyone?