An mkw file extension is related to the compressed audio format developed by Michael K. Weise.
MKW file extension - Compressed audio
What is mkw file? How to open mkw files?
File type specification:
The mkw file extension is associated with the compressed audio file format created by Michael K. Weise, no loss of quality as occurs with MP3, but they have large size.
The mkw file format seems to be obsolete product without support from developer, or producer.