Ask HN: How do I handle multiple currencies with Paypal?

I adding a feature on Disrupt.fm that will allow musicians to sell songs through the site. The musicians will enter in their paypal address in the backend and the purchase button will direct the user to Paypal's payment confirmation that will send the money to the artist. The problem is that about half of the traffic is international.

I'm a little confused about what currency to sell the songs in...here are the two options I'm thinking about:

1. Sell all songs in USD and have the artist incur any currency exchange fee if not US based.

2. Ask the musician what currency they would like to accept payments in when they enter their Paypal info. The problem with this is that I'll have to convert the price of the song ($0.99 USD) according to exchange rates when generating the paypal purchase button if the musician is not US based.

Any thoughts on how to go about this? Is anyone familiar with how Paypal handles exchange rates?