I am about 11 or 12 feet from my sensor bar, and my remotes work just fine. However, on the Wii Menu, I would sometimes notice a jittery cursor when It's in the lower right portion of my TV (I have a 65" HD TV).
I was figuring that it was some odd glare coming from the tv screen protective cover an bouncing off of the shiny front of the sensor bar windows.
SO, i places a sheet of kleenex tissue over the front of the sensor bar, and the remote now works flawlessly in all areas of the TV - even back to 15 feet or so. Obviously, the kleenex eliminates extraneous glare from the sensor bar windows.
Has anyone else done this? I am going to get 2 small patches of black, see-through fabric to put on the front of my sensor bar, so the fabric won't stand out...