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Audio-Stack-Configuration

Shawn edited this page 2026-05-19 23:07:19 -04:00

Table of Contents

• Audio Stack Configuration
• Target Configuration
• Kernel Command Line
• Services
• ALSA Configuration

Audio Stack Configuration

Target Configuration

Parameter	Value
Sample rate	48 kHz
Buffer size	128 frames (~2.7ms)
Periods	3
JACK priority	70 (server) / 80 (clients)
IRQ priority	95 (USB/xHCI)
CPU isolation	cores 1-3 for audio, core 0 for system
Round-trip latency	5-8ms
Max channels	16-18 @ 48kHz/24-bit

Kernel Command Line

console=tty1 quiet loglevel=3 threadirqs nohz_full=1-3 rcu_nocbs=1-3 isolcpus=1-3 usbcore.autosuspend=-1 fsck.mode=skip

Services

• jackd.service — JACK2 audio server (auto-start)
• mixer-api.service — REST/WebSocket/OSC API
• mixer-ui.service — Touchscreen UI (Kivy)
• cpu-performance.service — CPU governor lock
• mixer-firstboot.service — Setup wizard (disables after first run)

ALSA Configuration

• snd-usb-audio loaded as module
• alsa-usb.conf in /etc/modprobe.d/ for USB audio quirk handling
• Default device: hw:USB (configured by first-boot wizard)