I have an iPad 2 and can't seem to change the "new email" sound. It's stuck on "Motorcycle" even though it indicates whatever other sound I choose (i.e. Tri-tone). So, I can change the indicated sound but it still makes the motorcycle sound when a new email arrives. If I choose "none", then there is no sound, so that works.
I'm hoping there is a solution that doesn't involve resetting the device because I have many passwords and stuff saved in it and it would be a headache to redo them. Oh, and I just updated to the latest iOS version.