I wanted to post this little PSA in hopes it helps save someone a bit of frustration.
We recently switched our ISP (Internet Service Provider) and needed to buy a new router. We went with the ASUS RT-AC1200 router, which isn’t gigabit, but since our service’s bandwidth caps at 100 Mbps, we didn’t need the extra throughput.
For the most part, the router works great, but we did have some trouble with getting our Google Chromecast to work with the router. It had trouble keeping connected to the ASUS router. Even the setup via laptop or smartphone was difficult and wouldn’t finish successfully. Sometime we’d be able to see the Chromecast from other devices, and the Chromecast even indicated that it was connected to our network, but it we couldn’t cast with any reliability. I tried many things, and finally figured out the correct setting for the router.
Make sure the 2.4GHz access point is set to “Legacy”. Also, you may try disabling IPv6. If that doesn’t work, the last thing to try is to disable the router’s firewall feature.
After setting this, and rebooting the router, the Chromecast stays connected to the network and we can cast from all devices without problems!