Upgraded to SwOS 2.8. Now getting this:
CPU Temperature 67C
Board Temperature 0C
FAN1 0 RPM
FAN2 0 RPM
PSU1 526mA @ 26.65V

Fans aren't spinning. Were before and were quite noisy.

SwOS 2.7 reported temperature in and around 30 to 38 degrees and fan speed around 4000rpm.

RB3011 sitting on top of the 328 reports:
Voltage 25.9 V
Temperature 37 C

750Gr3 on top of the 3011 reports this:
Voltage 26.4 V
Temperature 43 C

CRS125 in same room but different area reports this:
Voltage 26.0 V
Temperature 29 C

I'm assuming I should be very worried and prepare an RMA? Room temperature is 19 degrees .

Hi, on some CRS328-POE we have the same bug!

Some switches updated normally, some are alive, but 0 RPM with 67-72 Temp

But there was no problem with cooling with 2.7p version, loudly - yes, but no 0 RPM :/

UPD
Well, the second repeat of update - partially, i think, solved the bug
temp decrease, health page now shows systemboard's temperature.

Can someone from Mikrotik explain this?

I’m out of the office now but thanks! I’ll try reinstalling the update and post my results here.

Forced a reboot of the switch and fans are working again!

CPU Temperature 39C
Board Temperature 35C
FAN1 4440 RPM
FAN2 4410 RPM

UPD2

On some devices after few hours after force reboot or update, I have the same problem.

60C CPU
0C Board
0 RPM
0 RPM

Because this switch in 2500 km from me, I don’t know about real cooling.

+ empty parameters in some excels in SFP+ tab

As I wrote earlier, force reboot, solves it, but that’s not normal situation, make reboots of the switch several times for the day.

CRS328-24P-4S+
SwOS 2.8

i found the same problem.

CPU Temperature : 61C
Board Temperature : 0C
FAN1 : 27648 RPM
FAN2 : 0 RPM

after reboot

CPU Temperature : 40C
Board Temperature : 30C
FAN1 : 4560 RPM
FAN2 : 4545 RPM

about 1-3 days will found the problem again.

Could you help me fix it, please?

The only thing that worked for me was to reboot the switch.

I had a power failure here recently and since the power came back I've had no issues since. It's very strange.

Have the same thing.

Does your software report as 2.7p or 2.8?

My CSS326 just arrived today to go alongside my CRS328 but the flaky SwOS behaviour is worrying...

Mine says 2.8 (built at Fri Jul 13 2018 12:37:17 GMT+0100 (IST))

However I see there is now an update available:

Latest Available Version 2.8 (built at Wed Oct 03 2018 07:02:09 GMT+0100 (IST))

Will upgrade later this evening and see how it goes.

Its firmware bug in SwOS, have a look here for more discussion:
viewtopic.php?t=132553#p685035

What I found was it was a very small PoE load that seemed to confuse it, now I a couple more devices 4-5w each the fans just run 24*7.

Its a worrying problem as once the fan control dies/crashes the fans never run and I found on several occasions the switch was getting very very hot to the touch so hate to think what the CPU temps were!

I gave up on SwOS in the end. Booted to RouterOS and haven't had any issues since.