Upload & Sell: On
Out of the hundreds of photography websites I've seen, I can think of maybe one of them whose experience has been enhanced by music. In the other 99.5% of cases, the music has been a distraction at best, and downright annoying at worst.
We all used to browse the internet on a desktop computer in the comfort and privacy of our homes (and occasionally offices) but given the increasing portability of computers that enable us to browse the internet in cafes, libraries, restaurants, airports, and other public places, it seems less and less like you'd want to invite a song to unexpectedly autoplay in a browser, causing embarrassment and annoyance to the user and people around them.
There are so many good reasons not to play music on a website. People have different tastes -- not everyone will like the music you play; people often listen to their own music while they're browsing the internet, which your music would definitely interfere with; people often multitask and so your window might not even be maximized when your music starts playing; and you're giving the impression that your website (or worse, the work featured on it) is not good enough without music.
The best websites -- the Googles, Facebooks, Amazons, Twitters, Ebays, Pinterests, Wikipedias, New York Times and Flickrs of the world -- do not use music. Why should you?