3.1 consists mostly of library updates and bugfixes. The main library used by the audio engine, ffmpeg, was updated from 2.7.3 all the way to 4.4. 2.7.3 was released over 5 years ago, so this is a pretty significant upgrade. The main reason behind the upgrade was to help with building a new audio engine. A new engine is a long way off but I have began prototyping one based off of ffmpeg 4.4. The 2 main drivers behind writing a new engine from scratch is to fully support hi-res audio and to support playback of other sources than just local files. Being able to play network files (samba/upnp/dlna) has been a desire for a long time and I'd also like to be able to support some of the popular media server software like Plex, Emby, and Jellyfin. My other app ( QuasiTV ) already interfaces with all 3 for video playback, so leveraging that code for audio playback would be pretty straight forward. When the engine does make its way into GMMP, it'll be in addition to the existing