Google has shared an update on the ongoing situation with its Chromecast (2nd gen) and Chromecast Audio devices that suddenly stopped working on March 9.

Google acknowledged that affected devices around the world were no longer responding in a Google Nest update on March 11, saying the company was aware of the outage and that it was working on a fix. Additionally, Google requested owners of affected devices not to factory reset their devices as a means of troubleshooting, but as you can probably imagine, by the time the post was live, many users had already attempted a factory reset.
Now, Google has put out a new update informing users that the disruption has been fixed. For users who factory reset their devices, the following will need to be done to get the device working again.
Google writes that users who factory reset their device must ensure their Google Home app is updated to the latest software version, specifically version 3.30.1.6 for Android and 3.30.106 for iOS. The app can be updated from its respective app marketplace: Play Store or the App Store.
If the app isn't updated to the latest version, the user won't be able to connect to the Chromecast device. Google writes that the update for the Google Home app may take a few days to roll out globally, but it will already be available to download for most users. Once the Google Home app has been updated, the user can perform the Chromecast setup as usual, and the device should work.