Volume can be adjusted either via the buttons or app. You can adjust how many ‘steps’ are changed per click/button push.

You can use it either as a pre or pass-through. You can configure the default volume on startup. Simply set that to 100 for pass-through and you’re good.

I’m of the opinion 24/192 is plenty.

Not sure on the DAC configuration. Would need Andrew’s input there.

The app does display album art. You can also. Customize the background. Can’t say I’ve mirrored it to a television but I can’t see why that wouldn’t work.