I asked this in another thread, alongside another question, but didn't get an answer to this one. I'm using a Universal Dock, which I was hoping would charge my iPod classic, however... it doesn't.

It charges fine when connected directly to the power cable (which is an Apple original, should that make a difference). It also charges fine when connected to my Mac via the USB cable. And when I connect the iPod to my Mac while it's in the dock, it works fine. However, when I connect the power cable to the dock and then place the iPod in it... nothing.

Is there something simple I'm not doing?