Just bought the ultra 4670 with latest firmware, 9.2. Attached WD 4TB hdd to USB port and it instantly recognized the drive and all my audio/video files. I am using Roku Media Player. Unit worked perfectly for 3 days. But, after disconnecting the USB cable to transfer files to my laptop, and reattaching USB cable to the Ultra, it no longer sees the hdd. I get the message "Waiting for media devices". Just to rule out the hdd, I attached it to my laptop and it recognized it, files and all, with no problem. I reset Ultra to factory defaults, uninstalled and reinstalled Roku Media Player with no success. Again, hard drive is perfectly fine on other devices. I'm stumped...Any ideas? Thanks so much! Also, hdd has its own AC power adapter so it's not being powered by the USB port. Edit:. Just attached a thumb drive to USB port on Ultra and it doesn't see it, either. Looks like I have a faulty USB port on the Ultra.