I recently got some Toshibas and they were loud. They also presented with a seek error pre-fail after a few days (all three of them). That propably adds to the volume, but the seagate and wds I switched to just have some clicking noises. Not too bad.
Not sure what Disk Manager is, but if it says
It appears to be something. If you do a
sudo journalctl -f
before you plug it in, does it tell you what device name it is given? If it is sata-to-usb you are using it is probably /dev/sd[a-z] or so, does anyone show up when you plug it in?