Based on that document, it looks like one drive is slightly under the max and 1 is slightly over it. I would check your ventilation. Many cases are designed to work most efficiently with the case closed. How many fans are in the case?
I shut down the server overnight, put the cover back on, and it’s pretty much the same: 56 and 58 C.
There’s a fan in the back of the the case. It doesn’t seem to be going full blast, probably because the CPU temperatures stay at 29 - 34 C. - assuming the fan is controlled at all. pwmconfig (linux) shows no controllable fan; sensors does not give fan speeds.
With the fan, power-supply, and side vents in the back, and the disk drives in the front, I’m not sure this is well designed for air-flow over the drives.
On the other hand, there are several reports of theses disks running hot in the amazon reviews on this unit. See here
Some quotes: “Only thing I realized is, it runs hot. like HOT”, “I also find that it gets incredibly hot very quickly, essentially turning my PC tower into a space heater”
Other reports there say that the idsk is very noisy, but I haven’t noticed that at all.
So maybe there are batches that differ from the others?
SO I took the cover off and placed a small USB powered fan blowing directly on the drives. This seems to keep them under 34 C. Not sure what a permanent fix is.