Latest results: after using the speakers for a couple of weeks they have STOPPED NEEDING TO BE PAIRED after I shut down the iMac or reboot either. I wish I could tell you why this wasn't the case earlier, but I haven't a clue. Anyway, never turning off the speakers who are cabled to the iMac headphones plug, w the green lite on the front of the speakers(pc/aux mode), and the speakers are working fine after rebooting or restarting. One other thing, these speakers have incredible sound.