At first I thought it was just my own personal preference not to have music while people are talking, but after reading some of the responses, I think that those of us with hearing problems really do find it difficult to sort the words out from the other sounds. I certainly wouldn’t want to discourage anyone from buying and learning from MBB 5, because there is a lot of good information there; those of us with hearing problems just have to work a little harder to understand it.
My recommendation to someone wanting to make an instructional video would be to include sounds, music, etc., as part of the introduction or in between sections, rather than as background while people are presenting their subject.