If you experience an invalid device error, you may need to clear cookies on your browser and then restart your device. Then please try the video tech test again in your Empatico account.
If you see the error screen below, please click the arrows highlighted in the image to select your audio and video. This should enable Empatico to access your camera and microphone.
If this does not resolve the issue, you may need to allow access to the camera and microphone through your operating system preferences. For Windows 10, please follow the instructions here: https://support.microsoft.com/en-us/help/13753/windows-10-camera-does-not-work. For Mac OS, please see the instructions here: https://support.apple.com/guide/mac-help/control-access-to-your-camera-on-mac-mchlf6d108da/mac.