A mysterious bug is affecting numerous older Chromecast devices, as per a lengthy thread on Reddit—specifically, the second-generation Chromecast and the Chromecast Audio, which both launched in September 2015. If you’ve been affected, hold off on trying a factory reset of your device.
The bug has started appearing over the last 24 hours, rendering affected devices pretty much unusable. One of the error messages reported reads as follows: “Untrusted device: [name] couldn’t be verified. This could be caused by outdated device firmware.”
Further investigation from users suggests that this is a server-side problem—so the issue is at Google’s end. It looks as though there have been complications with expired security certifications, so the Chromecast dongles that have been hit are being incorrectly identified as unsafe to connect to.
That means there’s nothing Chromecast owners can do for the time being, other than to sit tight and wait it out, without any streaming audio
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