Hi
This is my first time using balena, so sorry if this is very rudamental.
I have a setup with a Raspberry Pi Zero W and a Pirate Audio DAC 3w amplifier.
I have got the system up and running, and can connect with both airplay and spotify, but i’m getting no audio out.
Under Device variables i have changed Audio out to DAC and under Device configuration → Definee DT Overlays i have added “BALENA_HOST_CONFIG_dtoverlay=hifiberry-dac”
Any Ideas on why i’m getting no audio out?
After reeding the log more carefully, it seems like the DAC is not discovered, running aplay -L gives me the following:
bash-5.0# aplay -L
null
Discard all samples (playback) or generate zero samples (capture)
pulse
PulseAudio Sound Server
default
Default ALSA Output (currently PulseAudio Sound Server)
sysdefault:CARD=bcm2835-alsa
bcm2835 ALSA, bcm2835 ALSA
Default Audio Device
So it this a config thing or a hardware thing?
Hi
Does this device require external power or something? It would be nice to rule out any issues with the hardware connections.
Can you perhaps share a photo of your connections?
Hi Anuj, thanks for the reply.
After getting a bit annoyed yesterday i built a new image with mopidy, and with mopidy everything is working smoothly and audio is coming out. Mopidy on the other hand doesnt give me the functionality i want, so i will go back to Balena.
But, as everything work fine with mopidy im quite confident the hardware is working as it should.
So: no, externa power is not required, and i am powering it with a 3A charger, so the power should be more than enough.
Hi Thomas, I just checked the Pirate Audio DAC 3w amplifier documentation and found this which looks very interesting:
There is a DAC enable pin—BCM 25— that must be driven high to enable the DAC. You can do this by adding gpio=25=op,dh to the /boot/config.txt file.
Probably mopidy’s image is taking care of this while I’m sure we are not. I suspect the DAC is “offline” without that pin being driven high so that’s why it’s not being listed. It’s the first time I see a DAC that needs this, it might be it has this option to reduce power consumption, not really sure.
Anyways, there are two ways you can try this:
config.txt on your SD cardBALENA_HOST_CONFIG_gpio with a value of 25=op,dh
Let me know how this goes, if it does we’ll need to update our docs to include this special case.
BTW, I’m assuming this is the DAC: Pirate Audio: 3W Stereo Amp for Raspberry Pi – Pimoroni
Got it back to balena now, and that fix worked perfetcly, thanks 
And yes, that is thee correct DAC.