It depends where the .wav file is. If it is in your application’s data then you don’t need permission. If you need to access the SD Card (/mnt/sdcard for example) you’ll need READ_EXTERNAL_STORAGE permission. You can request this with the BP node. Once you have permission you can read from the directory with low-level file access (open, fopen, etc) from C++, or by using the UE4 file commands which will need the change from the quote to use absolute paths.