Answer:
1 Broken or malfunctioning keyboard: A broken key in your keyboard or a malfunctioning keyboard can cause such issues.
2 Problematic Keyboard Drivers: Outdated or corrupted keyboard drivers may trigger actions that make your computer alt tab on its own.
3Problematic Graphics Drivers: Corrupted graphics drivers may bug the overlay, which is likely why your games keep alt tabbing.
4Virus Or Malware: Virus and malware are known to take over applications and make them behave wierdly. This can be one of those situations.
5 A Task is running in the background: A task may be running in the background while you are playing a game on fullscreen. This may bug the task window and make it alt tab every few seconds.
6Background applications and services: Similar to a task running in the background, other applications, and services running in the background can also get bugged and alt tab on their own.
7Corrupted system files and outdated Windows: Outdated Windows and corrupted system files are also known instigators for such issue.
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