Found it!

Put A Penny In The Slot

For ages i've been trying to find this song. All i knew was that it plays in the bg in Jerry Maguire when he slips her strap off on the doorstep. Useless people (read Salvatore) that I requested should source the music for me got me Secret Garden and Aimee Mann instead. They're good songs but i wanted this.

It's the gentlest, softest piece of music ever. It's called Singalong Junk by Paul McCartney.