Your download is starting.

Install it

AppImage (any distribution): make it executable, then open it. In most file managers that's Properties → Permissions → Allow executing as a program. Or in a terminal: chmod +x lanaudio-*.AppImage, then run it.

.deb (Ubuntu, Debian, Mint, Pop!_OS): sudo apt install ./lanaudio-*.deb, then open lanaudio from your apps.

Set up the audio device

Click Set up audio device. lanaudio asks your sound system (PipeWire or PulseAudio) for a device called lanaudio. No password, no driver.

Send or listen

Sending: pick Monitor of … your speakers to send everything this computer plays, then press Start sending.

Listening: click the sender's name. In OBS, add Audio Input Capture (PulseAudio) → lanaudio.