Grammar in lyrics.

I have a notable collection of grammar pet peeves. Some of them are quite justified, but others are thoroughly silly. My example for the day is bad grammar in song lyrics. I can't stand it. Just now I was listening to a song with this line:

"So tell me when you hear my heart stop
You're the only one that knows"

It should be , "You're the only one who knows." The line refers to a person, not a thing, so it should be "who," not "that."

Every time I hear this in a song it bothers me. I'm trying to just enjoy the music, but as I sing along I hear the error and my singing stops. Can't help it. Is it really that hard to use the correct word? They have the same number of syllables and they don't need to rhyme with anything. Seems simple to me.

..........

See what I mean? Thoroughly silly thing to get annoyed by. But there it is.


P.S. The song quoted above is "Possibility" by Lykke Lie, in case anyone is wondering.