My server logs show someone has figured out how to access the config file of the "Google MP3 Audio Player" plugin on wordpress sites, and has set up a bot to seek these out. 91.236.213.74
It says: "many of these audio player plugins can easily be hacked into and the streamed mp3’s can be downloaded (you just need to ‘Inspect Element’ in Chrome and find the source URL). So I’d recommend not using the majority of these of you’re selling digital content!"