I'm going to take it that you have all fairing bolts in their place. Did you take a look at the fairing stay bolt? It's the one attaching the fairing brace to the downtube right below the top triple. If that's OK then I would consider the instrument panel itself. They are rubber mounted for some give and take. However, that movement has bothered me enough with a noise over bumps and I have added more or new foam weather strip around it like the bike comes new. Have also, for lack of better description, stuffed a piece of foam under the gauges. It's out of sight under there and offers support without making it too rigid. Some pipe wrap insulation cut to fit makes a good one.
Hope you get it sorted and good luck,
Roger