It was my understanding that Ogg files require more CPU power to decode than MP3 files. Perhaps one of the Cambridge guys will chime in here and clarify this.

In our codebase we have a really good ARM MP3 decoder and only a fairly good ARM Vorbis decoder. Perhaps Sharp have it the other way round. AIUI there's not much inherent difference in complexity between MP3 decoding and Vorbis decoding, except for really high-bitrate Vorbis files.

Peter