Which HiFiBerry DAC are you going to use? Looks like they have about a dozen different DACs and I'd love some guidance on what would probably be a decent default choice.
Also, you mentioned that volume control is a next step. For me, that feels like a pretty fundamental thing. Isn't that built-in to the Spotify, AirPlay protocols, and DNLA protocols?
For hifi use, the HiFiBerry DAC2 HD is reasonable. All the other HiFiBerry DACs are good "for the price" but not that great on an absolute scale.
You'd be much better off with a USB DAC. For example, the Topping D10s or the JDS Atom DAC+ are both about $100 and you're unlikely to be able to tell the difference between them and literally any other DAC available at a higher price.
One thing that doesn't seem immediately obvious with the HiFiBerry DAC+ ADC Pro I have is that input and output are separate devices.
I assumed it would be a checkbox or two, but I couldn't mix the input jack into the output without doing it in software, and PulseAudio would drop samples at lower latencies. I admit I didn't troubleshoot this very long though.
MPD, Bluetooth and an AUX input was all I wanted, and I could make it work for scenarios that didn't need the low latency part.
I bought the DAC2 Pro. I don't know if it's the right pick for me yet -- I guess I'll find out!
The part about volume control was a little ambiguous: I can absolutely control the volume via the "soft" controls in AirPlay, DLNA, or my desktop's own soft mixer. What I meant was the "main" volume control on the receiver itself, which is motorized and controllable via an IR remote.
It's kind of a non-issue since I can just set the receiver's volume sufficiently high and then moderate using the "soft" controls, but I thought it'd be fun to try and automate the main control as well.
Also, you mentioned that volume control is a next step. For me, that feels like a pretty fundamental thing. Isn't that built-in to the Spotify, AirPlay protocols, and DNLA protocols?