I have an iphone 4. Not too long ago, the computer that I had it synced to crashed - and all the music on it was lost. I have since bought a new laptop, but I can't put new music onto my iphone unless I buy it directly from itunes. I fear that this is because home sharing was never turned on when I had the other computer. Luckily, I backed up my iphone so I still have all that music. I just can't add any from my new laptop. Is there way to fix this?