I updated it to 1.8 today with my Android DJI Go App for my Phantom 4. After installing, the downlink became unstable and the display garbled from time to time. At first I thought it was just with my goggles connection, then I found out the same with my phone screen as well. Tested it back home and still found the video downlink unstable. Refreshed the drone firmware again but to no avail. Finally gave up and downgraded the firmware of the controller back to 1.56 and that solved all the issues. If the past experience is to go by, do not upgrade the firmware of a controller before you up grade the firmware of the drone. But on this occasion there is no upgrade for the drone firmware.