thanks for your explanations andrewilley! I did already read the Reddit article. My problem is that I can see the Android / data folder, but it appears empty, while I know that it is not because the SD card is indicated as containing 18 GB of data, not however of the audio type but of the "other" type. Do I need to reset my SD? But if I can't use the data stored on the SD or even load most of the apps in it, I wonder what I can still use it ...