We have found 2 software records in our database eligible for .mka to .flac file format conversion.
Matroska audio (.mka) files are often used to store movie audio tracks outside of more usual Matroska container, typically to store alternative language localization to a movie and so on.
In case you want to transform these tracks to FLAC format, i.e. perform mka to flac conversion, you will have to use to Freemake Audio Converter or similar program. Just keep in mind that the resulting quality won't improve, as the audio track within .mka file was probably compressed already with a lossy method.
MKA
Files with mka file extension can be typically found as audio files in Matroska audio file format. Pretty much same as MKV, but MKA is used for files that contain audio content only in Matroska container.
FLAC
Files with flac extension are used for audio files compressed with the FLAC, aka Free Lossless Audio Codec. FLAC files do not lose any quality with their compression as MP3 do, but they are generally larger. Most modern media players support playback of FLAC files.