Try the BD player on another HDMI port.
We own four Samsung BD-H6500 Blu-ray players in my extended family. Each of them are running the latest firmware 1107. Three of these players are connected to non-Samsung TVs, one is connected to a F series Samsung TV. After 10 minutes of video play using BBC iPlayer the Samsung Screensaver becomes active on the Blu-ray player. This only occurs on the Blu-ray player attached to a Samsung TV. Blu-ray players attached to TVs of other brands do not have this problem. This issue started on Firmware 1106. I expect that the Blu-Ray player is communicating to the Samsung TV that it is no longer active during iPlayer video play. Samsung, you make very products, but please make an effort to fix this issue. It is obviously affecting many people in the UK who have both the BD-H6500 and an F series Samsung Smart TV.

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