did you tried "Pan and Scan"?

mine using series 6 too, but is 32" and older model

i always use PS3 to watch anime and movies, most of the movies i watch is 16:10 and if the TV set to 16:9, both upper and lower part of the video will be crop, aka overscan.

so that's why now i'm using the "Pan and Scan" option and no more overscan, from what i see, if set to 16:9, the TV will be display the video in it's original respect ration, which means 16:10 will still be 16:10 but it will crop upper and lower part to become 16:9, hope i'm correct about this.