Well, a while back I bought a SanDisk 64Gb Micro SDXC card. I popped it into the phone, it was recognised straight away, it was formatted by the phone, and I saved a tonne of music to it. All was well for a while, but then I started to get playback issues. In short, music would plan but would intermittently pause, catch-up, pause again, catch-up again, etc.. It is awful. At first I thought it was a Bluetooth issue in my car, but I upgraded the car Bluetooth and it got no better. And then I noticed the same problem when using wired headphones. I've tried listening to music in flight-mode (the constant wireless scanning does the 'stuttering' effect sometimes) but it got no better. I tried killing as many apps as I dared, but it still happens. Does anyone know what the issue might be?