Due to a bug introduced in tvOS 15.4, if you have multiple Apple HomeKit Hubs (Apple TVs / HomePods), you may experience issues when viewing camera streams on Apple TV, for example, grey screens or messages saying 'Disconnected' or 'No Response'. You may also experience unreliability with HomeKit Secure Video event recording.
This issue is not specific to Starling Home Hub, and affects all cameras that connect to HomeKit via a bridge.
To work around this issue, you will need to enable a setting on Starling Home Hub which changes the way the hub adds cameras to HomeKit.
Publishing cameras as unbridged HomeKit accessories
First, on your iPhone or iPad, go to the Starling app, Advanced Settings, then enable Publish cameras as unbridged HomeKit accessories. This will temporarily remove your Nest cameras from HomeKit.
Then, after around a minute (to allow an iCloud sync), go to the Apple Home app on your iPhone or iPad, press ‘+’, Add Accessory, then scan the QR code on the base of the hub. This will re-add one camera. If you have more than one camera, press ‘+’, Add Accessory, then scan the QR code on the base of the hub again to add the second camera, and repeat until all the cameras have been re-added.
If you later add a new Nest camera to your account, you will need to add it manually to HomeKit by going to the Apple Home app, '+', Add Accessory, then scan the QR code on the base of the hub again.