I have brand new batteries in the remote. If the TV is turned off and I press any button on the remote control, the sensor light on the front of the DirectTv DVR blinks, however as soon as the TV is on, the sensor doesn't blink and the guide, menu etc. won't come up. If you stand directly in front of the box(about 2 inches away) and hold the remote underneath the TV you can get it to receive the command and get the guide, menu recording options.
I will ask about the RF option.