Javascript error "listen EADDRINUSE: address already in use"

[holmesworcester]

I see this on startup now.

Uncaught Exception:
Error: listen EADDRINUSE: address already in use :::3435
at Server.setupListenHandle [as _listen2] (net.js:1318:16)
at listenInCluster (net.js:1366:12)
at Server.listen (net.js:1452:7)
at new WebSocketServer (/Applications/Zbay.app/Contents/Resources/app.asar/node_modules/ws/lib/websocket-server.js:74:20)
at Object.exports.createServer (/Applications/Zbay.app/Contents/Resources/app.asar/dist/main/websockets/server.js:6:20)
at /Applications/Zbay.app/Contents/Resources/app.asar/dist/main/main.js:374:42
at step (/Applications/Zbay.app/Contents/Resources/app.asar/dist/main/main.js:52:23)
at Object.next (/Applications/Zbay.app/Contents/Resources/app.asar/dist/main/main.js:33:53)
at fulfilled (/Applications/Zbay.app/Contents/Resources/app.asar/dist/main/main.js:24:58)
at processTicksAndRejections (internal/process/task_queues.js:93:5)