I'm going to assume you have a UN55ES6500. I find this very surprising that the XBox will work on all inputs, but both the Blu-ray player and U-verse STB will only work on the ARC input. What are the model numbers for the Blu-ray player and the U-verse STB?
Just purchased a samsung 55es6500 3d smart tv. I have att unverse cable box, samsung blue ray player, and xbox im trying to hook up. Also have a boston accoustic sound bar. xbox will work in any hdmi inputs. blue ray player and att unverse cable box will only work in the hdmi arc input, but only have one hdmi arc input. this is very annoying. soundbar hooked up with optical wire. not sure why att unverse wont work on other hdmi inputs because we had it hooked up to an older flat panel with no hdmi arc and it worked just fine. can anyone help, please?