My Birdy has developed an irritating and noisy clanking whenever I ride over anything but the smoothest surfaces. By comparison, even the cheapest budget bikes don't make any noise when they riding over the same roads, so it's doubly irritating.
I've had a very good look around the rear of the bike but can't find anything obvious. The cable tap and the chain can slap against the frame if I ride over a major hump, but I don't. All bolts seem to be tight.
My LBS have had a look and think it might be the SRAM Dual Drive, which would need to be sent away.
Before I do that, does anyone have any other suggestions?