Here's what I did....

And just the other day, I took delivery of a brand spanking new KVM switch from IOGear, it was $49.00 and works like a dream....

Alternately, you can use VNC to control your music box from your main system, it works well too but not as reactive as a hard-wired KVM switch.

I used WinXP for both my machines, it means that my music box also can fill in for my main system if need be in an emergency....