This is a known but rarely acknowledged fault. First off, don't mess with your tv picture settings to make this work, could never understand why BT would advise people to degrade their picture settings just to get their remote to work. Surely everyone wants optimal picture settings on their tv, not a degraded setup which would be a backwards step.
I had a plasma tv which possibly could've been the cause of the remote not working correctly as since upgrading my telly to a new Panasonic LED I've had zero issues.
One solution (albeit a tad messy) which worked for me while I had the plasma was to tape a small piece of white card in front of the BT box IR sensor (I kid you not).
The IR sensor is on the right side of the box as you look at it and is about an inch or so in from the edge of the box fairly close to the blue internet light. I was advised to shine a torch through the front display to locate the exact position of the sensor. An archaic solution but it did work for me at the time I needed it.
