Disable System Sounds in Editor

I'm using SceneGUI to detect keypresses in an editor tool I'm working on.

The tool functions perfectly but when I use certain button combinations, I get the system beep sound effect that warns that my key press is invalid.

Does anyone know if there a way to tell Unity, or the system, that my key presses are valid and prevent the system warning sound from playing?

I'm on Windows.

EDIT

This appears to only happen when I use alt + key combination. I think windows uses alt + key for menu shortcuts, but beeps at you if there is no valid menu for your input... so annoying!

Would love to know if anyone has a way to prevent this beep from playing.