GRT Sport EFIS Troubleshooting Failures

Phase 1 test flying is going well. Everything getting dialed in smoothly up until my last flight. EFIS screen blacked-out and froze. This left me with no working transponder, using my EIS for my flight data, and phone for gps. Thought it might be an isolated event, but soon discovered it was not. Everything works just long enough to make you think it is fixed. Went out again right before take-off the next day. This video is primarily for GRT to take a look at it. Any thoughts or ideas are appreciated!