I have a complete desktop setup now with my SP3. Monitor, wireless (USB) keyboard and mouse, USB powered speakers, USB connection to monitor (for touchscreen capabilities), and a hard drive. I have one open USB 3.0 port on the dock. So this is the problem. Every so often I get a message in the system tray that states "USB Controller Resources Exceeded". Sometimes when that happens, I get no sound out of the speakers. But if I disconnect all devices and add them back, the sound usually comes back. I'm sure the speakers must be part of the problem, but I have had all ports taken before and I tried another pair of AC powered speakers - and I did get the same message. Wondering if its the USB dongle for the keyboard and mouse because if I attach it directly to the tablet (which I would like to avoid) everything works fine. Any thoughts?