Drives continuously unmount in the Mobius Thunderbolt 2.

Make sure all drives are fully seated into the bays and check that the screws attaching drives to trays are all fully tightened.

Additionally, it has been reported that Mac OS X's Spotlight function may cause these issues. Disabling Spotlight from searching the drives may resolve the problem. To do this, go to System Preferences > Spotlight > Privacy. Then, click the (+) button and select the drives to be added to the list of locations you do not want Spotlight to access.