Sounds to me like you have a hardware problem with your installation. If you need to fiddle then you've probably not selected adequate speakers for your listening patterns.

I get pounding bass when appropriate and live-sounding voice when that's called for. All without ever having to retune anything.

If you need to boost your bass at high volumes, then you're not running appropriate drivers. Or you're trying to lower the frequency of songs that were never meant to go low to begin with.

If you create a few EQ presets, you can just toggle between those much more easily than having to fiddle with bass and treble sliders. Have you tried this? You'll likely find that you have enough presets to be able to account for whatever changes you'd manually make to treble/bass anyway (most of those controls don't have many "clicks" anyway).

That's my 2cents...

Bruno