Does anyone know how I can put my Xperia z1 back to jellybean?? I have recently done the update to kit kat 4.4.4 and it's completely ruined my phones performance. It overheats, battery drains super fast, apps keep randomly closing,it goes back to the home screen. But most importantly to me the phone will NOT allow me to transfer media ALL of my photos to the micro sd card (which has 64gb of storage space!!) the phone just keeps telling me internal memory full transfer media to sd card. But it 's just not letting me?! Somebody somewhere please please please throw some light on this subject for me. I'm desperate!! Thank you.