Wow, I've never talked to anyone in Broome before. Thats a first!

Not to get book-ish, but the aileron starts to buzz because air turbulence in flight matches the "natural frequency" of the aileron and linkage causing the amplitude to grow dramatically as the system absorbs energy from the air. The match in frequency we call "resonance". Stiffening the aileron system will increase its natural frequency above and beyond any ability of the turbulence to match it and create a resonant condition. OK, thats the theory......

What everyone else has mentioned is all good advice and what they are essentially saying is "stiffen the system". Looking at the photo of your model I can see that the aileron linkage to the servo is rather floppy piece of music wire with a kink in it - shorten or at least stiffen that and for heaven sake lose that kink! As MTK mentioned, carbon tube with a piece of 4-40 threaded rod JBWelded in each end makes a very stiff pushrod. Also, looking at the aileron I see its a strip type with the linkage at one end. if you hold one end of the aileron you can probably twist the entire thing into a helix from the other - attaching your servo link to the middle of that instead of at one end will increase the stiffness too by shortening the lever arm. You might even consider replacing the ailerons with something that has better rigidity or gluing another strip of aileron stock to the one thats already there.

Finally, there is one thing that no one else has discussed and its a long-shot but worth mentioning. The fact that you are only having trouble with the right side suggests there may be something upstream causing an inordinate amount of turbulence feeding directly into that RH aileron. Exhaust? Good luck! Let us know how you fixed it.