@Capt'n Corrupt: you are giving away your age if you remember those types of remotes, lol. But spot on, I'm envisaging a matchbox sized device with a highly selective audio filter that converts audio pulse train to IR. It would have the advantage of being cheap and not requiring additional hw (such as some BT/networked device). All assuming the RC codes can be captured or dl'ed somewhere. I am not an audio engineer though and suspect some specialist equipment is needed to test if this idea would be feasible.