I have a Lenovo Think Centre low profile computer on W7 and I am using it as a media Centre for a 40” TV. I fitted a TBS 6281 Dual DVB-T2 tuner card and used Windows Media Centre to control it. I have fitted a Radeon HD6450 Graphics card and attempted to set this up to get sound over HDMI, which this card supports. When I activate the sound over HDMI, I get an error message from Media Centre telling me that the Video Codec’s are wrong and it refuses to show any picture or sound. The only way I can get anything to work is to activate the onboard Realtek graphics to deal with the sound via a pair of small computer speakers. Then I have to reset the Media Centre from scratch (Which takes for ever) and we get picture and sound, but with lip-synching problems which get worse if I watch any HD TV channels. I have read many many forums on this subject, but none of the answers seems to correlate with my set up, so don't have any effect. Any ideas before I blow several fuses in my brain.