I held off on installing any updates for a while, but I'm on the latest release of 8569 (A13) and it seems to be working properly now, thanks!
This issue appeared in the last version (6.0.1.8432 I believe) but it's still present in the newest release (6.0.1.8555) of the Realtek HD Audio drivers. I have to keep reinstalling an older driver (8216 is the most recent one I could find) to have MaxxAudio working The problem is MaxxAudio does nothing in the new drivers. The control panel software is still there (and it's updated too, because there are a few changes like having an Earbuds option instead of Headphones Small), but the audio isn't being affected. It's not active because the speakers sound weak and tinny (which is why I need it - it makes them sound ok) and none of the controls change this. Turning it on and off, turning knobs or moving sliders, nothing. Multiple reboots haven't changed this If I reinstall the 8216 driver, after a warning about how it's an older version, everything works fine. These newer drivers don't. I'd like to update - especially since there's been an urgent update - but as far as I'm concerned having MaxxAudio working is a requirement. Plus it automatically updated again in the background last night, not sure how, but if that keeps happening it's going to be a problem Is this where you report bugs, or can someone pass it on to the team? I can give you more information if you need it, but I don't really know where to start troubleshooting this (This is on an XPS 9560, Windows 10 1803)  
MaxxAudio not working in the latest Realtek drivers (8555)