Volumio and HifiBerry Digi+ Pro

I’ve just started trying to get a HiFiBerry Digi+ Pro to work and am having some difficulties.

My setup is a volumio installation with the digi+ pro connected to a DacMagic (optical but have also tried the coax). I’ve not been able to get any sound output and, on occasion, see the following error on the volumio web UI:

“Failed to open “alsa” [alsa]; Failed to open ALSA device “hw:1,0”: No such file or directory”.

So far I’ve tried both a RPi2 and an RPi3 with same result, so fairly confident it’s not the Pi. Have also tried Max2Play and that works so that eliminates any hardware issue with the Pi or the HiFiBerry.

Some posts in the forums here seemed to indicate that setting the audio out back to headphone jack, rebooting and then setting back to I2C might help but sadly that hasn’t worked.

[EDIT]
Running volumio 2.362 Released: Mon Feb 12 02:29:28 CET

Searching the forums at HiFiBerry led to me to run “aplay -l” and the output there looks promising:

**** List of PLAYBACK Hardware Devices ****
card 0: ALSA [bcm2835 ALSA], device 0: bcm2835 ALSA [bcm2835 ALSA]
Subdevices: 8/8
Subdevice #0: subdevice #0
Subdevice #1: subdevice #1
Subdevice #2: subdevice #2
Subdevice #3: subdevice #3
Subdevice #4: subdevice #4
Subdevice #5: subdevice #5
Subdevice #6: subdevice #6
Subdevice #7: subdevice #7
card 0: ALSA [bcm2835 ALSA], device 1: bcm2835 ALSA [bcm2835 IEC958/HDMI]
Subdevices: 1/1
Subdevice #0: subdevice #0
card 1: sndrpihifiberry [snd_rpi_hifiberry_digi], device 0: HiFiBerry Digi+ Pro HiFi wm8804-spdif-0 []
Subdevices: 1/1
Subdevice #0: subdevice #0

[ Further EDIT]
Just ran the same aplay -l directly after seeing the error in the volumio web UI and get this output:

aplay -l
**** List of PLAYBACK Hardware Devices ****
card 0: ALSA [bcm2835 ALSA], device 0: bcm2835 ALSA [bcm2835 ALSA]
Subdevices: 7/8
Subdevice #0: subdevice #0
Subdevice #1: subdevice #1
Subdevice #2: subdevice #2
Subdevice #3: subdevice #3
Subdevice #4: subdevice #4
Subdevice #5: subdevice #5
Subdevice #6: subdevice #6
Subdevice #7: subdevice #7
card 0: ALSA [bcm2835 ALSA], device 1: bcm2835 ALSA [bcm2835 IEC958/HDMI]
Subdevices: 1/1
Subdevice #0: subdevice #0

i.e. card 1 is no longer there. That looks suspicious!

Any tips for some diagnostic steps to follow much appreciated!

Thanks.

SOLVED

The problem was with the 7" Display that I had attached (the official Raspberry Pi one). It turns out that connecting the SDA and SCL pins from the GPIO header interferes with the Digi+ Pro, which makes sense as these are I2C pins. The good news is that disconnecting these two pins doesn’t impact the display.