2008 ZX6R bought new last April, broke it in properly for the first 500, currently at 12,000 miles with regular maintenance and oil changes. The valve adjustment and tune up is due at 15,000 miles...

So recently at 10,000 rpms it makes a howling sound: in any gear, speeding up or slowing down to 10k, and constantly if held at 10k. At first I thought it was the wind catching a vent in my helmet and making a sound, but it's definitely coming from the bike. Any ideas? It's still under warranty, should I just take it in?