Okay,i was going to stay out of this post at first,because it seamed that all the advice being given was reasonable and could help. But it seam's as this post goes on,everyone is overlooking the one thing to me that is the most obvious. I have built and flown,numerous Carl Golberg Ultimate bipes over the years. If built exactly according to the plans,they are light and fly great! Only draw back is,that after a year or two of flying they tend to get structurely weak in the wings! Any slightest rough or bumpy landing will and usually does cause seperation of the trailing edge of the from the wing ribs. It's not easily seen or felt because only one or two ribs let lose. They also tend to break the outer wing strut mounting ribs. All of these will cause the flutter you are getting. It's not caused by you linkages being lose,the aileron hinges being bad, or servos going bad ( providing all those were checked and confirmed as okay). Your flutter is coming from the fact that the wing panel is actually moving,while in flight. The most obvious give away,was your saying,that it got so bad you had to trim it out to land. Surface flutter of any kind,CANNOT be trimmed out!

I learned this lesson the hard way on the ultimate's! lol Since my autopsy of my first one,showed the defects,i built the rest of them reinforcing the trailing edge's. And have since never had a repeat of the first.

Hope this info help's

Art