I was able to replicate it. I can consistently do it if I change sequence settings + enable/disable renderer in Adobe Premiere. I let it run to a pool and have confirmed, its a false positive. They are running at 65mh, not 87mh. Here is the video showing all of that in 3 minutes.
https://youtu.be/viSrcMcWwtUThe good thing is that he was honest to the very end, so it is confirmed it was a bug, 6800 or 6900 both have equal hashrate, so that means cache does not help with eth mining at moment, might help on other algos, it needs to be tested. Thanks for the link.