I have a late 2013 iMac with several seagate desktop drives attached via USB 3. They all used to work great, even through the Mavericks update. But now one volume keeps ejecting itself whenever I try to write to it. Reading is fine, but once I try to move a file to the drive, it fails and Finder sends a notification telling me a "disk was not ejected properly, please eject the disk before disconnecting". Then the disk usually remounts and shows back up in Finder, but sometimes never remounts and needs to be unplugged and reinserted. Console gives these logs as I try to write a file: I tried reformatting, erasing, and a firmware update on the drive but this issue still persists. Any ideas?