It's a massive issue to me, Vodafone don't give me unlimited data so I try to have my frequently listened music stored offline. I only like high quality audio (obviously). Lost count of how many times I've had to do a complete uninstall just to get it storing to the SD card and not internal memory. I've only got to update the app to have everything stored offline erased and repeat the long patience testing process. other things can also cause my offlined content to disappear, resetting my phone for example. Highly annoying - love the app, but absolutely hate this issue. HTC one m8