I recently upgraded to a 1080p television and was excited to try out the 1080p passthrough mode. However, I have noticeable lip sync issues using 1080p mode. It seems to be limited to 1080p passthrough mode. I am passing the hdmi to an AV receiver to my TV. The audio is coming from the AV system. Because the problem it is limited to passthrough mode I don't want to insert any delay into the receiver. Any thoughts or suggestions would be appreciated.