I solved my own problem - Should I be embarassed to be caught like this? Anyhow, if you put your FLAC files into the S3's standard music directory "Music" on your external SD card, there's no problem: Poweramp finds your FLAC files and puts them into its library and album listing automatically as soon as you disconnect the USB cable. BUT, if you (originally, when you first set up your S3) just copied your "My Music" directory from your Windows box to your S3, keeping the directory name "My Music", Poweramp has a lot of trouble recognizing the FLAC files in it although it doesn't have any probl