'servicing' the remote control isn't an especially high priority on the DVR. If it is busy doing something else (I have no idea what, but I have seen it happen many times). It does in fact 'save' the button press and queues them. What usually happens is you end up pushing the buttons many times because nothing happens, and at some point, the DVR suddenly processes all of the queued remote control button presses.
You can tell if the remote control button was recognized because if it is, the power light on the QIP 7232-2 will flash to indicate the command has been received. If nothing happens immediately, it generally means for whatever reason the DVR is buy doing something else, and will get around to processing the command eventually. If you keep pressing the buttons, it queues them up, and later executes ALL of THEM!