Hello, we’re FIPE Labs. Some built-in audio codecs that can be distributed free of charge are not embedded in FX Player. In order to use such codecs, you can purchase and install them following the below procedure. [External Codec Installation Procedure] 1. Download codec to smartphone. 2. Access FX Player [Settings] and check [Use External Codecs].3. Check message saying [Codec has been found].4. Restart player. FIPE Labs will always do our best to provide better service for you. Thank you.