I read that if its plugged into a computer it will "pair" via bluetooth with that computer. The thing is I want it to be wired. Bluetooth can be inconsistent, especially on my old mac. I'd like to just leave it plugged in always. Will it use the cable as the connection if I do this? And yes I already have the wired keyboard with the numerical keypad. The problem is that using a mouse with that keyboard causes your arm to stick to far out and over years causes incredible arm pain. I often use a left handed mouse to combat this. I would like to get the one without the numerical pad so that I can switch hands.