Well peaking didn't make it any better. This is as good as it gets. It seem like sunny weather is always the worst for signal around here. Had to go Lowe's and get some new U-bolts, because of loosening and tweaking and then retighten them again, I just ripped 'em off. A loud bang and off the nut goes.
. And by the way: Yes the mast is grounded too. The whole Unistrut array is grounded, so the mast must be grounded too. The paint on the mast around the clamps is scraped off too, because I aim the antenna like a rotator, and turn the mast, not the antenna. This helps, because I don't have to go all the way up the roof all the time. The nuts and bolt heads are so tight, that any paint got scraped off while tightening. So there's electrical contact everywhere. The dish is grounded too. The grounding blocks of the antenna and the dish are grounded at entry of house with #8 copper. Dish and antenna have seperate grounding blocks, and both are attached straight to the main grounding rod.