I have not had or heard of that happening.. Though I must admit "Do" #2's wing noise
make me think something going to fly off, But all's hanging on so far after tons of hard flying.
I'm sure your wing bolts were completely tight... what about stripped bolts..

My last outting with 6 flts on the "Do" did great... My tank tightening did not reduce my wing
harmonics... But my engine area seems to be staying cleaner???? I did shorten my breather to
just below the cowl???? It was fun... Ohh my SPAD got it's first streamer on a 3 plane combat))
that's a lot harder than I thought it would be.... Loads of fun... We are shooting for 8 planes next
weekend:-) The plyon racing has been on hold they all say my spad is to fast to be fair, but
they are working on that))....
A snow bird member that I trained last year brought his 60 "Do".. He was telling me how his
makes a lot on noise too..... NOT..... I can see why too, the rib spacing is a lot closer on the 60...
That made me start peeling the wing covering on my spare wing......