Please make sure the keyboard and mouse are connected to with the right port. 

That is the keyboard must be connected to with the lower below USB port, and the mouse must be connected to the upper USB port.

If the mouse is connected to the right port but still can not work well, please try to press hot key by following steps. 

1. Invoke Hotkey Setting Mode. 

    1-1 Press and hold [Num Lock] 

    1-2 Press and release [-] 

    1-3 Release [Num Lock] 

    Please note that the above 3 steps must be completed in 0.5 sec 

Morevoer, Iif your KVM is set to use [ctrl] and [F12] to invoke Hotkey Setting Mode, please use [Crtl] replace [Num Lock], [F12] replace [-], and then follow the same sequence to invoke Hotkey Setting Mode. 

2. Press [M] set mouse to bypass mode

 

Also, you can check the manual from following website for more information about the hot key operation https://www.aten.com/global/en/supportcenter/downloads/?q=CS782DP

If the issue persists after doing all things above, please contact our Tech Support for assistance.