I'm having trouble with my recently purchased AOC Envision L22W898. It has been working perfectly, but now every time I turn it on it defaults to the AV input, in which nothing is plugged in. When I bring up the input list to try and switch to another input, the list only has HDMI and PC listed. I have nothing plugged into the PC slot and an xBox 360 plugged into the HDMI slot. When I switch to the HDMI slot with the 360 on, the screen goes white and nothing happens. The menu won't open, I can't adjust the channel or volume, and I can't switch to any inputs besides HDMI, PC and AV. I've tried unplugging various things from the TV and unplugged power to the TV for 5 minutes to try and reset it, but nothing seems to work. What can I do?