Using pulseaudio with a Fe-Pi Stereo Sound Card on the Raspberry PI3

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Introduction

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This article describes how to set up pulseaudio, an advanced sound server for Linux, with a Fe-Pi stereo sound card and use it in conjunction with fldigi or direwolf digital modes software.

Prerequisites

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* A raspberry pi 3B+ (or similar model)

* Rasbian Jessie operating system installed on the Raspberry Pi

* PulseAudio not already installed on your raspberry pi

Hardware Setup

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1. Connect two speakers to your Raspberry PI's audio/video 3.5mm socket.

Software Installation and Configuration

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### Install necessary packages

Firstly, ensure that you have the following package installed:

sudo apt-get update -y && \

sudo apt-get install --no-install-recommends pulseaudio libpulse0 oss4-alsa -y

### Configure Pulse Audio to Use ALSA Driver.

To tell PulseAudio that it should be using the sound card via alsa driver, you need to add this line at the bottom of /etc/pulse/daemon.conf:

# Tell pulseaudio to use your soundcard (in my case 0)

default.pcm = 'alsa'

exit-on-signal=2

### Restart Pulse Audio and/or Start it if not already running.

Finally, restart or start up PulseAudio by entering these commands in the terminal window on your Raspberry Pi:

sudo service pulseaudio --start &

Configuration for fldigi/direwolf

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You may need to configure `fldrigi`/`direwolf` to use ALSA as its audio backend instead of OSS. To do this, you can add these lines at the bottom of your ~\ .fldigrc or ~/.direwlrcc configuration files:

# Set up fldigi/direwolf to use PulseAudio

device = 'alsa:default'

### Restart Your Digital Mode Software

Finally restart your digital mode software by exiting and re-starting it.

Troubleshooting Tips:

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If you find that the audio coming out of one speaker is reversed, then try setting this line in `~/.config/pulse/daemon.conf`:

# Swap left and right channels

alsa.default.channels = 2

Then restart PulseAudio by entering these commands into your terminal window on your Raspberry PI:

Raspberry pi 3 pulseaudio