Help w/USB problem?

I wonder if someone can help ID a problem I'm having. I can't properly mount any USB devices -- e.g., iPod, digital camera, or portable USB drive. They all show up OK in the System Profiler, but they simply don't mount. However, my USB-mounted printer still works properly.

I've tried swapping devices into different USB slots & doing reboots. Also, this started happening around the time I put in a new wireless router (Belkin N+), which has a USB port for network storage, but the problem persists if I take the router out of the loop.

Please pardon if this is an obvious problem. Any ideas how to fix?

Run the Apple Hardware Test on your machine. Sounds like your USB ports are not providing power. The printer will continue to work from the port because it doesn't draw power from it, only print signal(s).

Regards.