I’ve bought another Genesis on ebay to test. I don’t have any composite cables to test. The unit only came with the RF connector. I did try to plug in to just the component slot with the green cable and got black and white video. Tested composite with green/red and green/blue and got original results of black screen with flashes of green but no glimpses of actual video from the console. I’ve also tried different games just to eliminate that as a problem. Not sure if this helps troubleshoot.