The default hotkey for KeyPad is Command+ Option + P. You can change this hotkey from the preferences screen.
Click on the KeyPad icon in the toolbar, and select Preferences.
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In the preferences screen, select the device that you want to change the shortcut key for.
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Click on Configure HotKey button. This will allow you to select a hotkey to replace the current HotKey. Notice that the text changes to Select HotKey using Keyboard.
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Press the hotkey that you would like to use. It is recommend that you use a combination of keys like Command + Option + keystroke. If you use a keystroke that is already handled by the Mac it will not trigger the application.
In this example I pressed Command + Option + O.
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Notice also that the Configure HotKey button has become un-selected. This is an indication that the keyboard shortcut has been set correctly. You can have a separate hotkey for all your devices.