On rare occasions, Drew's Dad or I will accidentally put the "wrong" ear on Drew. We'll put his right on his left or vice versa. Each of Drew's processors is specifically programmed for an individual ear. For some CI users, their programs on each ear are nearly identical, so mixing them up won't create too many problems. Sure, hearing won't be maximized, but there isn't any tell tale sign that there is an issue.
That's not the case for Drew. His maps on his two ears are quite different. His right ear requires so much power that we actually had to go to a wider pulse width than his left ear. As a result, mixing up his right ear and putting it on his left causes him pain. It is "too loud", as he has told us in the past. And we always know when we've put the right ear on his left because he cries out in pain.
Now that Drew is a bit older, we were able to ask him after this most recent mix up what putting on the wrong ear actually sounded like. Here is Drew's response: