I have Airport Extreme Base Station 802.11n with USB port. I formatted a powered HDD for Mac OS Extended (HFS+). I successfully used it as an air disk for a few months via a non-powered USB port. Then suddenly the drive kept disconnecting and connecting up again. I ignored it for a while and just dealt with it as a nuisance. I thought my HDD was failing and blew it off. Recently after the 7.6.1 upgrade, I noticed that the HDD was not being seen in the Airport Utility. I connected the USB directly to my MBP and saw that the drive was still functioning properly. I verified the drive with Disk Utility so think the HDD is okay. I connected the HDD direct to the USB and bypassed the USB hub to no avail. I'm suspecting that the USB port must be dead. Has anyone experienced this before? How can I verify if USB port on AE is working or not? Can I replace USB port? Help!