OGG
MKV files
OGG is a container format that can multiplex various independent streams for audio, video, text, and metadata. The audio component often uses the Vorbis compression algorithm.
MKV (Matroska Video) is an open, free multimedia container format that can store video, audio, and subtitles. It is known for its flexibility and support for various codecs.
More MKV conversions available on this site