I signed up for the zune pass trial in hopes to have random mixes from an artist/songs i chose. However, when I choose smart dj on the phone, it just scrolls through music i already have on the phone and does not play similar type music like pandora/iheart/slacker would. Does Zune only play music you have on the phone? or will it play random mixes off of what you already have. This will make a big difference on whether I pay for a subscription. Appreciate any advice.