I have been playing with the duration and it has not helped so far. The RFX9600 is receiving the commands, but there seems to be a delay in the IR transmitter because that light does not go on. For example when I press the down button repeatedly the busy light is on, but the IR light only turns on for every other press. Basically it's only consistent if I wait 2 seconds between each press. Also I cannot hold down the button and keep going down the guide, like I can with the original remote.

(BTW I know it's not the cable box because I can go down very fast with the original remote)