Watching movies & Backlight issue

[Deltatristar500]

Hi, has anyone had this issue happen when watching a movie on the 800W, with the micro USB slitter where I can charge the phone and watch a movie at the same time with the stero headphones, the phone starts to get hot and the back light will turn off. The movie will still be playing but will be harder to see since the backlight turned off, when I take the charger plug away from the phone, in a couple of seconds the back light will turn back on and I can contiue watching.....has anyone else experisnced this and is there a solution to this? Could the phone just be getting too hot?

Thanks