Pulse Audio Configuration for Raspberry Pi Audio Systems

This Pulse Audio configuration is designed to sit between your audio source and sink, to keep the audio device open and mitigate speaker pops.

This is only for I2S DAC devices on the Raspberry Pi that pop when they are started/stopped.

Installing

First, install pulseaudio if it's not already installed:

sudo apt update
sudo apt install pulseaudio

/etc/pulse/client.conf

Edit /etc/pulse/client.conf and add or change these lines (anything preceeded with ";" is commented out so be sure to remove it):

You can edit a file with sudo nano /etc/pulse/client.conf and find lines by pressing Ctrl+W, typing your search term and hitting enter.

autospawn = no
default-server = unix:/tmp/pulseaudio.socket

/etc/pulse/default.pa

Edit /etc/pulse/default.pa and find the line load-module module-suspend-on-idle, add timeout=604800 onto the end.

It should look like this:

### Automatically suspend sinks/sources that become idle for too long
load-module module-suspend-on-idle timeout=604800

Next, find the line load-module module-native-protocol-tcp and add auth-ip-acl=127.0.0.1 to the end.

It should look like this:

### Allow local connections over tcp, for mopidy etc
load-module module-native-protocol-tcp auth-ip-acl=127.0.0.1

Then, find the line load-module module-native-protocol-unix and add auth-anonymous=1 socket=/tmp/pulseaudio.socket.

It should look like this:

### Allow unauthenticated connections from other users so aplay, etc work via pulse
load-module module-native-protocol-unix auth-anonymous=1 socket=/tmp/pulseaudio.socket

If you want to use a VU Meter

If you're using Pi VU Meter with pHAT BEAT, Speaker pHAT or other compatible board then find the line that starts ### Automatically load driver modules and add the following before it:

load-module module-alsa-sink device=pivumeter

This will make sure Pulse outputs through the VU Meter plugin, rather than right to the audio device.

/etc/systemd/system/pulseaudio.service

Finally the pulseaudio.service file:

[Unit]
Description=PulseAudio Daemon
After=sound.target
Requires=sound.target

[Install]
WantedBy=default.target

[Service]
Restart=always
Type=simple
PrivateTmp=false
ExecStart=/usr/bin/pulseaudio --realtime --disallow-exit --no-cpu-limit --log-target=syslog
ExecStop=/usr/bin/pulseaudio --kill

Should go into /etc/systemd/system/pulseaudio.service and be enabled with:

sudo systemctl daemon-reload
sudo systemctl enable pulseaudio
sudo systemctl start pulseaudio

Verifying

Check that pulse is running by entering:

sudo systemctl status pulseaudio

This will also show you any relevant log output.

Tips & Tricks

Fix Choppy Audio When Streaming

One possible fix for this problem- particularly with Shairport Sync -is to disable WiFi power management.

You can test this by running sudo iw wlan0 set power_save off and, if it works, make it permenant by editing /etc/network/interfaces and:

allow-hotplug wlan0
iface wlan0 inet manual
    wpa-conf /etc/wpa_supplicant/wpa_supplicant.conf
    wireless-power off # <---- Adding this line

Troubleshooting

First, double check that you followed all the config steps above correctly.

A useful troubleshooting tool is aplay, you can usee aplay -L to show a list of device names, including pulseaudio if it's running.

No sound when running pulseaudio

Try restarting your audio applications, and ensure they're outputting audio via pulse. This pulse configuration will tie up the raw sound device (by necessity to keep the clock running) and all sound must go via the daemon.

Check aplay --list-devices, if you have more than one device listed here your audio might be playing to the other one, or pulse might have selected the wrong device as its sink.