Software Bug or Hardware faulty MikroTik-CRS309-1G-8S+

Hi,

I noticed MikroTik-CRS309-1G-8S+ When SFP-sfpplus2 port is disabled/device is shutdown or module is unplugged I get SFP-sfpplus1 “TX Fault” error. (error goes on and off).
When SFP-sfpplus1, sfp-sfpplus2 is both are active i don’t get "TX Fault on SFP-sfpplus1 ".

Is this software bug or normal behavior on MikroTik-CRS309-1G-8S+ or is it defective?
Installed version: 6.43


DAC

Fiber

Firmware 6.44.2 upgrade seems to fix that particular problem.