We tested this and were able to reproduce, although it works normally with Windows and macOS. This may be related to OS + your motherboard's UEFI USB power management settings and are investigating...

@t sornin To clarify, the issue is with the 10-bay remaining active? I will have to report this for testing.

@Jeff morris It should be a relatively simple matter, it's possible the surveillance system formatted them this way. Hopefully support can fix that easily.

@mad-jester Yes. You should absolutely get firmware from technical support to see if it helps.

@ted.lillys Yes, there might be a reason for but it would require testing. It could be a facet of the internals or based on how power is sensed through USB. Auto-HDMI switches often act similarly.

Thanks for info. The weird part is mine used to default to the A port - I've had the switch for more than a year and in the last 2-3 months started to default to the B.  My default set up used...

HI, these drives are WD Purple which came out of a surveylance system we upgraded the drives on. They have no current data on them and I was intending to use them as individual backup drives, thus ...

I own the 5 bay and the 10 bay units, both run on the same linux box.  When the server is shutdown, the 5 bay will turn the fan off, and the leds go on the front of the unit will turn red, and...

@Sabrent Could it be that my DS-4SSD is also "improperly identified" and is actually supposed to have TRIM?..

@mad-jester One issue we're seeing is that the product ID shown in programs like USB Device Tree Viewer seems to be incorrect and it may be properly identified with a firmware update. We began test...

@Jeff morris I'm confused as to why each drive has the exact same partition layout. I am not sure what your intention is with these drives and if there is any data on them. If the drives are clear ...

@ted.lillys We tested a unit in the office and it also defaults to the B port. The power port provides the standard 900mA at 5V.

Care to elaborate on the additional testing?

Thank you for the answers! "This model" - do you mean EC-UASP or DS-4SSD? A firmware update can't bring TRIM support into JMS561U, right? At which capacity should I be worried about the limitation...

Appreciate the response. Unfortuantely the 3721.42GB partition is not allowing me to right-click and assign a drive. Everything is grayed out with no formatting available nor assigning a drive, so ...

@mad-jester I will investigate this, thank you. Edit: None of our DS-4SSDs were shipped with a JMS561U. 

@mad-jester The EC-UASP can use multiple chipsets such as the JMS578 and ASM1053E. These do support UASP and TRIM. If you have any issues with capacity, as may be the case, a firmware update from t...

@Jeff morris Partitions don't have drive letters by default, you have to assign them. Each of four drives has a 3721.42GB partition which could be right-clicked for assignment, if that is your goal.

Unfortunately, I will be sending this back if I am not able to get the pathway corrected so the drives will work. Hope to hear from you today!

@Rick Raborn I was looking at some specs and noticed this enclosure had an update so was looking for a changelog and found this post. What staff should have told you is that the bronze thing is a s...