I have my server set up to transcode music files down to 160kbps before sending to my Android device using the Subsonic app. However, when the file's cover art is a .png format file, it does not transcode. The mp3 will appear on the device as if it is transcoded and cached, but no "download progress" indicator appears beforehand. It's basically skipping the transcode and download if the cover art is a png format image. If I use mp3tag to "cut and paste" the cover art so it saves as a jpeg, the issue goes away.