I just set up Raspbian, loaded drivers for my HifiBerry DAC+ and configured MPD.
Though I can’t get hardware mixing to work. Could anyone please help me with this?
I tried using mixer_control "PCM", "Digital Playback" (like in Volumio) and "Master" (like in some forum post I found) but nothing worked.
$ uname -a
Linux pi 3.18.9-v7+ #767 SMP PREEMPT Sat Mar 7 21:52:35 GMT 2015 armv7l GNU/Linux
$ aplay -l
**** List of PLAYBACK Hardware Devices ****
card 0: sndrpihifiberry [snd_rpi_hifiberry_dacplus], device 0: HiFiBerry DAC+ HiFi pcm512x-hifi-0 
Subdevice #0: subdevice #0
If you need any more information please feel free to just ask.
Thanks for your help!