NSA325v2 Multi HDD problems?

MrMonkey

Have a NSA325v2 running v4.81 fw and 2 HDD's 

1. WD Red 2.0TB - WD20EFRX (12VDC: 0.45A)
2. WD Red 4.0TB - WD40EFAX (12VDC: 0.28A)

if i use only 1 HDD at a time, both work no problem, either bay
inserting both at the same time, only the 2tb spins up when powering on

tried hotswapping the disk and the other disk LED goes red, sounds like the HDD physically stops (aint doing that again)

have formatted both disks and only one can be used at a time, both work fine on its own and can be mounted so im out of ideas besides a power supply problem but the power supply delivers 12v at 5amps so should be enough, unless faulty?

Mijzelf

You did actually measure that it can deliver 5A at 12V? That it delivers 12V without load doesn't say everything. Ideally you should open the case, and measure on the PCB what the 12V does when you power on the box. And yes, it's feasible that a power supply wears out over years, and can no longer provide the specified current.

And even if the power supply is fine, the disks also need a certain current on 5V. The PCB has some DC/DC converter for that. If that DC/DC converter cannot cope with 2 disks anymore, you are in trouble, as it's not easy to exchange. If that is the problem, you can possibly measure that on the USB 5V, as I suppose it's the same source.