I've been having the same problem lately and I haven't even changed locations. It seems like the entire network has slowed down. I used to be able to download at 15 KB/s on average, and now I usually get "needs more sources." When it does download, it is usually at 1 KB/s. There's an obvious change in service.

Try entering the title of the song in the search section again. Sometimes I find that if I'm downloading something and it says "needs more sources," if I search for it again, it locates another source. Usually it will only find one or two hosts, so your download might be slow, but it's better than nothing. Hope this helps!