One of the primary issues with a fiber transceiver is the cleanliness of the fiber connection.  The smallest speck of dust can lead to digital breakup within the transmission.It is recommended that every time you connect a fiber cable to your device, you clean both the cable and the transceiver unit.  A fiber optic cleaning pen can do both the male and female ends and can be purchased from several online retailers.  An example of a cleaning pen can be found here: https://www.amazon.com/gp/product/B01N760UBP/ref=oh_aui_detailpage_o01_s00?ie=UTF8&psc=1