http://www.techradar.com/news/your-chromecast-might-be-strangling-your-home-wi-fi-network

If you've been experiencing Wi-Fi dropouts and slow speeds on your home network recently, certain Google devices might be to blame according to several users in the Google Home Help Forum, as reported by Android Police.

One anonymous user in the forum started a thread after noticing that their Wi-Fi network had started dropping out with alarming frequency upon returning home with an Android device. As an experiment, the user disconnected their Google Cast-enabled devices from the network, including an Android handset, multiple Chromecasts and Google Home Mini units. The result? A stable network that has had no dropouts or issues since.