Since the 10.11.2 update my late 2012 mini can not mount usb disks. My external HD is seen in disk utility but can not be mounted. I can erase it, but can not partition it or mount it. I can do both in recovery mode. USB sticks dont even show up in disk utility. My ipod shuffle is also not mounting. I have no idea what else to try. I have tried SMC, and PRAM resets. Plugging in and unplugging everything. Using hubs and not. Everything was fine before this last update.