Hi, @Siobhan Allen
First, check whether the purple flashing also happens outside Zoom or Teams.
Open the built-in Windows "Camera" app and watch the video for a minute. If it flashes purple there too, the issue is more likely related to the camera driver or hardware.
Also try restarting the PC, then go to Settings > Windows Update and install any available updates, including optional driver updates.
To help narrow down the issue:
- Does the purple flashing happen in the Windows Camera app too?
- Is this the built-in laptop camera or an external USB webcam?
- Did this start after a Windows update, driver update, or any other change?
Also, what is the make and model of your PC or webcam?
Click "Add comment" to let me know.
Thanks!