Comment 21 for bug 1332722

Update:

Some absolutes seem to be that:
a) This is a Linux Mint issue (other distros work fine)
b) This is a usb 3 issue (plugging drive into a usb 2 port works fine)
c) NTFS volumes work fine (other filesystems disconnect).

I am wondering if this has anything to do with external usb 3 drives being 'win' devices without the knowledge of the owner.
In other words, NTFS is programmed into the usb->sata controller in your external drive case.

Also, I tested a drive with EXT4 and no LUKS encryption, same issue occurs.
Only NTFS never disconnects.