Hi,
Thank for your reactivity,
The Headphone designed has been well improved. I prefer this one to the previous on. But for the "M" I really prefer the previous one. With the understanding of be close to sound wave it makes full sens.
About the fontstyle: I do not like it that much. May be a style more round will be better. I also think that you can do something aroud the idea of sound wave (add graphical element around te brand name may be, even if i am not sure of the result). Good inspiration.
Regards,
François