- Company: Sony
- Samples: http://samples.mplayerhq.hu/A-codecs/MSV/ or using the following google search 
MSV files are Sony's Memory Stick Compressed Voice format.
The second version called MSV (LPEC) uses a proprietary Sony codec called Long-term Predicted Excitation Coding . It looks this codec is also used in another file format, called Digital Voice File (extension .dvf).
The file is made of 1024 byte packets starting with
00 xbyte 00 0A 04 00 0E 30 81 cbyte
where xbyte is variable and cbyte increases every 4 packets except the first packet which starts with "MS_VOICE" (in the single file we have now ...)