1. Why is my Chromecast / Android TV / Google Cast-enabled device not discovered?
Perform troubleshooting steps 1-6 listed in this answer.
If the issue persists, then you may need to check that your router is configured to properly allow Google Cast traffic. Most home networks don’t require any special configuration, but sometimes you may need to change a setting or two on your router to allow streaming on your network. The link below lists compatible routers as well as the most commonly needed configuration changes on many popular home routers.
2. When I stream HD videos (mostly 1080p & above) to my Chromecast 1st & 2nd gen, the playback sometimes freezes. How can I fix that?
This is a known, memory-related issue with Chromecast 1st & 2nd generation. When you play your content at a very high bitrate, the Chromecast Default Media Receiver can sometimes run out of memory available to it, which can either result in freezing or poor playback experience (it may manifest as buffering).
Disconnect your Chromecast from the app.
Open JustStream Preferences. Go to the Streaming tab and decrease the video quality and/or bitrate.
Reconnect your Chromecast with the app and stream that video again.
Video streaming should be working alright again.