I was pretty sure it was Kenny G that they were playing in the metro, on the chair lift at Fragrant Hills, and at a lot of other random places in China. So I checked wikipedia, which says in part:
Kenny G has recorded some Chinese songs, such as "Jasmine Flower" (茉莉花) or "The Moon Represents My Heart" (月亮代表我的心). His music is noticeably popular in China. His recording "Going Home" is often played at closing time at public places or at the end of classes at schools. Mass transit systems in Tianjin and Shanghai play these songs when trains approach terminus stations.
It's pretty insidious, that "Going Home". It's still stuck in my head, and I haven't actually heard it in weeks.