If your Device Manager is constantly flashing, blinking, or refreshing, it’s usually because Windows is detecting a hardware change. Essentially, a device is repeatedly connecting and disconnecting, forcing the system to re-scan its entire hardware list.
The phrase "Device Manager flashing" refers to a common Windows issue where the window continuously refreshes or flickers, often accompanied by a system beep. This typically indicates that the operating system is caught in a loop of detecting and then losing a hardware connection. Core Causes device manager flashing