Ed Cryer wrote:

The main difference that leaps out at me is that the 4TB drive has a
power adaptor; none of the other devices do.

Ed

As I understand it, it's a 12V @ 1.5A adapter.

My enclosures here use 12V @ 2A adapters,
with the intention of some of that being
converted to +5V inside the enclosure.

But it's pretty hard to guess why it only
happens when the drive is plugged in hot.

If there's nothing in the Reliability Monitor
for the events (except some sort of dirty shutdown
report), then it probably isn't a driver.
If it was a driver, the box should tip over
during the boot process when it tries to
mount the partition.

The power adapter "floats" and isn't tied to safety
ground. The GND from the adapter is tied to
logic ground, and there isn't really a mechanism
for something coming through the adapter
to tip things over. If the adapter went
crazy, it would likely burn the drive
and leave evidence.

It's almost like the bus charging transient
when the USB3 plug goes in, is enough to cause
+5VSB on the PC to wink out.

Paul