Just bought a Kindle Fire HD yesterday, and I've experienced this about 10 times already. After about 15 minutes of use, sometimes less, my touchscreen stops responding. It's like it freezes, but it isn't frozen because if I rotate my device, the screen still rotates. I just can't do anything on the screen; the only thing I'm able to do on the device is adjust the volume on the side and turn it off. When I turn it off, I turn it back on in 5 seconds, unlock it, and it works fine..until it happens again another 10 minutes later. Anyone else experience this? Is it a known issue, and is there a workaround? Thanks in advance!