https://github.com/paroj/DSub2000 [https://github.com/paroj/DSub2000] (https://github.com/paroj/DSub2000).

Two DSub2000 devices on the same Wi-Fi network can be linked so that one device (D1) controls playback on the other (D2). D2 streams audio from its own Subsonic server; D1 acts as a remote control.

On D2 (the device that will play audio):

1. Open Settings → Playback → Remote Control
2. Enable Local Control Server
3. Note the Local Server Port (default: 4040)

On D1 (the device that will act as remote):

1. Open Settings → Playback → Remote Control
2. Set Remote Client Host to D2's local IP address
3. Set Remote Client Port to match D2's server port (default: 4040)

1. On D1, tap the cast icon in the top bar
2. Select Remote DSub2000 from the list
3. Browse and queue music on D1 as usual — playback happens on D2
4. All now-playing controls on D1 work remotely:
   • Play / Pause
   • Previous / Next track
   • Seek — drag the progress bar to jump to any position
   • Volume control

D1's now-playing screen reflects D2's current playback position (updated every 2 seconds).

• Both devices must be on the same local Wi-Fi network
• D2 must have a valid Subsonic server configured — it streams audio using its own server connection
• Song metadata (title, artist, album) is sent by D1 so D2's now-playing screen displays correctly even if D2 is connected to a different server

This is why we need the permissions we do:

• Foreground Service - For downloading your playlists to cache
• Read & Write External Storage - Store the music cache on a sdcard
• Access Fine Location - Automatic day/ night mode and different server URL in local WiFi
• Read Phone State - Auto-pause playback when a call is received