Roon Knob

Custom firmware and a Roon extension that turn a Waveshare ESP32-S3 Knob into a dedicated Roon controller.

See what's playing, adjust volume, skip tracks, and switch zones—all from a physical knob on your desk.

Click to watch video demo

What You Need

1. Hardware: Waveshare ESP32-S3-Knob-Touch-LCD-1.8 (~$50)
2. Roon Core running on your network
3. Docker host (NAS, Raspberry Pi, always-on computer) to run the Roon extension

Quick Start

New to Docker or ESP32 devices? See the Getting Started from Scratch guide for detailed step-by-step instructions.

1. Flash the Firmware (one-time)

Download roon_knob.bin from the latest release and flash it to your knob:

pip install esptool
esptool.py --chip esp32s3 -p /dev/tty.usbmodem101 -b 460800 \
  --before default-reset --after hard-reset \
  write_flash 0x10000 roon_knob.bin

(Adjust the port for your system—see release notes for details.)

After this initial flash, future updates happen automatically over WiFi.

2. Run the Roon Extension

The extension connects Roon to your knob. On a Docker host (NAS, Raspberry Pi, etc.):

# docker-compose.yml
services:
  roon-knob-bridge:
    image: muness/roon-extension-knob:latest
    restart: unless-stopped
    network_mode: host
    volumes:
      - roon-knob-bridge-data:/home/node/app/data  # Persists Roon pairing token

volumes:
  roon-knob-bridge-data:

Image tags: Use latest for stable releases, or edge for bleeding-edge builds from master.

Volume: The data volume stores your Roon pairing token. Without it, you'd need to re-authorize in Roon after every container restart.

docker compose up -d

3. Authorize in Roon

Go to Roon → Settings → Extensions and enable "Roon Knob Bridge".

4. Set Up the Knob

Power on the knob. It creates a WiFi network called "roon-knob-setup". Connect to it, enter your WiFi credentials, and you're done.

The knob finds the extension automatically via mDNS.

Controls

Action	What it does
Turn the knob	Volume up/down
Press the knob	Open zone picker
Tap the screen	Play/pause
Swipe up	Art mode (hide controls, show album art)
Swipe down	Exit art mode
Long-press zone name	Settings

Features

• Real-time now playing with album artwork
• Velocity-sensitive volume control (turn slow for fine adjustment, fast for quick jumps)
• Multi-zone support
• Automatic display dimming and sleep
• Over-the-air firmware updates
• WiFi setup via captive portal
• Bluetooth mode for non-Roon devices

Bluetooth Mode

When you're away from your Roon setup, the knob can control any Bluetooth audio device (phone, DAP, etc.).

To enter Bluetooth mode:

1. Press the knob to open the zone picker
2. Select "Bluetooth" from the zone list
3. Pair your phone/DAP with two Bluetooth devices:
   • "Knob control" (BLE HID) - for sending commands to your device
   • "Knob info" (Classic BT) - for receiving track metadata from your device

Controls in Bluetooth mode:

• Turn knob: Volume up/down
• Tap play/pause button: Play/pause
• Tap prev/next buttons: Previous/next track

What you'll see:

• With both connections: Full control + track info (title, artist, album, progress)
• With "Knob control" only: Full control, but no track metadata
• With "Knob info" only: Track info displayed, but controls won't work

To exit Bluetooth mode:

• Press the knob and confirm "Exit Bluetooth"

Compatibility notes:

• Some devices (especially DAPs) can only connect to one Bluetooth profile at a time. In that case, connect "Knob control" for controls and skip "Knob info".
• The AVRCP implementation is controller-only (no audio sink), which may not work with all devices. This is why metadata is an optional second connection.
• WiFi is disabled in Bluetooth mode to save power.

Troubleshooting

Display shows	Meaning
"WiFi: Setup Mode"	Connect to "roon-knob-setup" network to configure WiFi
"Extension: Searching..."	Looking for the extension—make sure it's running
"Extension: Connected"	Ready to use

If mDNS doesn't work on your network, enter the extension URL manually in Settings (long-press zone name).

Development

See DEVELOPMENT.md for building firmware, running the PC simulator, and contributing.

Support

Questions or issues? Open an issue, join the Roon Community discussion, or buy me a coffee.

Acknowledgments

Thanks to gTunes from the Roon community for alpha testing, detailed feedback, and help with the velocity-sensitive volume control implementation.