Buzzing noise past 6K RPM from front/dash area

[advman]

I've put small plastic/zip ties (tightly) on my lamp adjusters, something still buzzes/rattles..

[stevesweetz]

the windscreen brackets that are on the height adjustment slider also jiggle around all day...

Taping those down was the first thing I tried.  They do indeed visibly jiggle around, but they're not the source of the noise. 
Sadly my headlight adjuster theory was bust.  I jammed them up pretty good and I still got the buzz.
 
I give up.  I have to fall back on my previous theory of it being something behind the dash.  I don't feel like taking the whole front end apart.
 
Whenever I go for an extended ride I wear earplugs and don't hear it anyway.  It's only an annoyance if I'm going on a short local trip without my plugs.

[Henchman]

So when I wind the bike up past 6000RPM I'm getting a plasticy sounding buzz somewhere up in the front of the bike, either from the dash or somewhere in the fork tunnel area. 
Something up there must be a little lose and ratting around.  I thought it was the little plastic brackets on the windscreen adjuster (which seem to be completely pointless!) - which you can see wobble around, but I taped them down as a test and it's not them.
 
Anyone know a typical culprit for this kind of rattle/buzz?

I noticed a new rattle/buzz show up in the dash area while at idle. Very loud and very annoying. I checked all the recommended areas but to no avail, until I grabbed the top of my windscreen and pulled it back toward the cockpit and the buzzing stopped. 
Turns out that it was my Cal-Sci tinted shorty windscreen that for some reason was now making contact with the mounting plate at the bottom of the screen, and pulling on the top spread that gap and stopped it from making contact. My remedy was to put a piece of thin foam rubber between the screen and plate and the buzz is gone!
 
Here is a view from the top looking down behind the screen.