He says, "Sometimes you play me a melody..."

The story:

Actually, I thought it was "melody", and a lot of sheet music has it as "melody", but Billy Joel's official sheet music has the correct "memory". If you listen closely, he does indeed say "memory." However, this is a universal Misheard Lyric that even the pros get wrong.

I also always sing it "Sometimes you play me..." even though I know it's "Son, can you play me..." I guess it just trips off my tongue easier.