Well not to argue anything here with Irish because my ears suck. But I noticed that first gear engagement was very harsh like it was shifted into gear with out the use of the clutch.Irish correct me if I am wrong here but say if it's not the Tube nut wouldn't it make the noise in the hub with the bike in Neutral if it was the drive? :dontknow:
I had the tube nut back off on my 08 at 1300 miles or 2092 km. It had symptoms like yours that started just a few miles or km before it finally backed off enough to cause problems and I had to ride home one night in 2nd gear. When I made it home anytime I shifted into gear it just died.
Listan 1 has a great write up on how to repair this if you feel up to it on your own. Just a few common tools needed. The only real thing that you must have is an impact gun and a 30mm socket. I was able to do the repair on the kickstand. I unbolted the exhaust and just swung them out of the way and laid them on a towel. 3 hours worth of work and 45 minutes was having to go to town and buy a 30mm socket for my impact gun.
Here is the link.
http://www.m109riders.com/forums/showthread.php?t=82993
Anyway with all of the info here and on the board if you feel up to it and have the mechanical ability you can do this yourself and not have to pay anyone to do it. Here in the states the dealers have either charged or offered half price to repair the tube nut issue as Suzuki does not want to take any responsibility with the issue. I think very few if any actually got it done under warranty.