Hi guys, hoping someone can help here... I have an iPhone 5, and sometimes I buy songs directly on it via the iTunes app. However, when I'm out and about (the only time i really use it to listen to music), often these songs are greyed-out, with the iCloud symbol next to them, and when I tap the icon it asks if I want to download the song over mobile data (I don't have unlimited data). Why does this happen? I've downloaded it once, why do I need to do it again repeatedly? There is still plenty of space on my phone. It's getting really annoying, how can I get all my songs to permanently stay physically on my phone..? Any assistance gratefully received!