Alsa-USB

Effortless USB audio support for Retropie + EmulationStation

Installation

Download the install script by running:

wget -N https://raw.githubusercontent.com/SaberMage/Alsa-USB/main/install.sh && chmod +x install.sh && bash install.sh

The terminal will clear and show a number of messages as installation proceeds
At the end of installation, you will be prompted to press a key. Your device will then reboot
Alsa-USB is ready to roll!

Default behavior: USB audio is enabled when connected, onboard audio is enabled when USB disconnects
Changes to audio output only occur outside of gameplay
Behavior, USB volume, and audio device can all be modified from the Alsa-USB menu, now found under EmulationStation Home->Configs

Note: Alsa-USB is compatible with Naprosnia's RetroPie BGM Player

Processes, apps and games must all be restarted in order to switch to/from USB audio. There is no known or anticipated fix for this
Because of this, audio device swaps will not occur or trigger any process restarts during gameplay. You must exit to the EmulationStation menu or restart the device for changes to take effect
Alsa-USB was tested on a 4GB Raspberry Pi 4B housed in a PiBoy DMG. Two different USB audio devices have been tested thoroughly over the course of development
If you have a USB audio device that doesn't jive with Alsa-USB, please let me know! I will do my best to add support for it, if I can.

All files you need are in each directory under /nexus
For each directory, there is a file beginning with __ - The text following __ indicates the parent directory path (where commas are slashes)
Some directory names have a prefix. The prefix indicates the necessary file operations:
A_ is for append - File(s') contents should be inserted into the correspondingly-named and located file
S_ is for symlink - File(s) here contain ,, in their names. Before ,, is the filepath for a symlink to be created. After ,, is the linked file
(no prefix) - File(s) simply need copied into a directory, overwriting any existing file(s) of the same name(s)

So, to install:

Download the install files by running: sudo mkdir ~/au-install && cd ~/au-install && sudo git clone --depth 1 "https://github.com/SaberMage/Alsa-USB" && sudo rm -rf ./Alsa-USB/.git && sudo chmod 777 -R ./Alsa-USB && cd ./Alsa-USB
Visit the first directory under /nexus
Perform the corresponding file operations
Repeat steps 2 and 3 above for each of the remaining directories under /nexus, until all have been processed
Run cd ~ && sudo rm -rf ./au-install to cleanup the install files
Reboot the device

Menu screenshots are in the works!