When replacing the GFI, there is a LOAD side and a LINE side. Remove the BAD GFI and make note of which wire are hooked to the LINE and LOAD side. Then leave the black and the white wires exposed in air and separated. Then with power on, check to see which is hot. That will be the LINE side. Kill power, install and check to see if that fixes your problem. Hope that helps and work safely...
2014 FR3 25DS (Bought 2-22-2014)