So, I have a Sony MZ-r700 and did a few shows where someone recorded my set. They sent me the mini discs and I tryed to play them in my MZ-R700. THey wont play, and the screen say "HD-MD..." Odd, because that isn't anywhere in the manual. Does this mean I just can't play the disc, or is there a mode I can go into. I have no clue what the HD MD thing is. Is HD a better sound quality? Or, does it just refer to the speed it records in, or maybe how much space is used on the mini disc?