Discs 8, 9, and 10 are CD versions of the original cassette tape releases by MOVIC. I don't know anything more about the tapes, but the pseudo track titles reminded me of the fact that old media used to have A and B sides. I bet many of the current younger generation fans never even saw a cassette tape. I feel old....
This tape, urr, CD, contains variety of "messages," like answering machine message, wake up message, etc., however, it's done in a drama format. The theme of the drama is basically Megumi going around the ship to collect voice samples to supply to the parent company.