Yes, that is the softswitch I was referring to.
The Port light on the Huawei modem (AKA the ONT) will flash quickly whenever there is data flowing and less frequently when no apparent data is flowing (e.g. watch it as you load a page with (say) lots of graphics or play a game online and compare that with how often it flashes when the page loading or the online game is finished.
Check the lights on the ONT, particularly PON and LOS, PON should be absolutely rock solid and ON where LOS should be rock solid and OFF), if you see even the slightest flashing on either then check that the Fibre and the DC plug are securely plugged into the ONT and haven't been knocked
