Pi Zero Phat Dac & Shairport-sync: Failed to find mixer element


#1

Hi,

I just made a fresh Jessie lite install of a RaspberryPi zero with pHAT DAC.
The installation of the pHAT DAC seems to be fine, passing the test.
Then I installed shairpoint-sync according to the guide: https://github.com/mikebrady/shairport-sync/blob/master/README.md
When trying to start shairport-sync I get the error: Failed to find mixer element
The /etc/shairport-sync.conf file contains:
output_device = “default”;
mixer_control_name = “PCM”;
running the alsamixer reports: "This sounds device does not have any controls."
Card: snd_rpi_hifiberry_dac
but Item: is blank

Any ideas what could be wrong?

BR Jacob


#2

I’m not familiar with shairport-sync enough to make much suggestion to troubleshoot the issue pertinently but glancing over the instructions that can’t be your configuration file in full?

I would verify the syntax, and if you can’t spot any error then post it here, preferably formatted as code so it is clear what is enclosed within curly brackets.


#3

I had a look at the shairport-sync sample config file to see if I could work out what might be the problem. I see:

//  output_device = "default"; // the name of the alsa output device. Use "alsamixer" or "aplay" to find out the names of devices, mixers, etc.
//  mixer_control_name = "PCM"; // the name of the mixer to use to adjust output volume. If not specified, volume in adjusted in software.
//  mixer_device = "default"; // the mixer_device default is whatever the output_device is. Normally you wouldn't have to use this.

so I think you need to (re)comment out the mixer_control_name line as there is no hardware volume control on the pHAT DAC.


#4

Commenting out the mixer_control_name and mixer_device solved the problem:
output_device = "default";
// mixer_control_name = "PCM";
// mixer_device = "default";

Thanks for the prompt answer!