Geez, how many ways posts does it take to discuss how to reboot?
Neither RBR and MRB are incorrect.
Sometimes one way works where the other does not.
If DTV didn't want you to have those abilities they would not have installed the features.
And a huge FYI on rebooting, usually when you call DTV with a technical issue, they will have you unplug the recvr for about 30 sec then plug it back in to reboot it.
So, that being said, try all three.
Is it always slow or occasionally slow?
I have an H24 in RF mode.
The receiver responds slowly occasionally but it is rare and really not a problem.
I keep mine in RF because I have the recvr hooked to multiple TV's (single guy and there is no need to pay for multiple receivers).
First suggestion for you though is if you can, put the remote back in to IR mode as it does work better and the batteries will last longer.
Do this anyways to see if the problem continues. If so, then you will eliminate weather the remote being in RF mode is the cause of the problem.
If it works fine in IR mode then you could get a set of IR repeaters.
Or try calling Direct TV and see if they will replace the recvr.
If it still causes the problem, then call direct tv and see if they will replace the recvr.
I have hooked several H24's and HR24's in RF mode with no problems.
But it sounds like you have tried just about everything else.