Failing to Access cambium PTP670 using PC

Hi all,
Mine is a bit of an electronics or technical problem, we have been experiencing common access failures with our PTP670 devices. They do power up when connected to the power adapter and all LED luminate as expected but, once the PC is connected to gain access to the device, there seems to be no communication between the two. checking status of ethernet properties shows that data is sent and no data is received from the PTP670.

because this seems to be more of an electronics problem, we would like to know which electronic part on the board might need to be changed? Note: we have a workshop with experienced and capable technicians for repairs.