I have a rev A Mac mini at 1.42 ghz. I bought an iPod shuffle a few days ago. I leave it plugged in so it keeps a constant charge until I am ready to use it. I cannot put my mini into sleep mode while it is plugged in because it cannot charge. Something weird happened this morning. I noticed that my shuffle had a flashing amber light on it. I thought that was strange since it had been plugged in all night. I checked in iTunes, and sure enough it said no iPod connected. I tried resetting the shuffle to no avail. Thinking it was the USB port, I plugged in my keyboard. The keyboard did not work. At this point I thought my 2nd USB port was fried. That didn't make sense. I rebooted my mac and its working again. Has anyone else had this problem, and if so what is causing it? Thanks.