I know I will never bear the white-hot intensity of your love for music, Vaya.
In my case, out of the blue I'll start humming or singing a song in my head (or out loud when I'm in the shower -- doesn't everyone?), and then my conscious mind catches up and realises that the same song is playing on the radio or the PA system. Just somewhere in the background.
The corollary of this is that I get irritated whenever a riff or a sequence will set off a song, but then my conscious mind runs up and tells me that no, it's really another one. One of those hip-hop songs that oh-so-cleverly grafts new words onto an older song, or another lacklustre cover out to milk adolescents for money.