The [CTRL][LEFT SHIFT][{PC Number from 1 to 4}][ENTER] keystroke combination lets you switch between PCs. Switching between machines can also be done by the front panel button. It might look a little cheap, but the fact is you are going to have 15 cables sticking out of the thing, so you're going to hide it if you have any sense at all, and so how it looks will make no difference.
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