One notable thing about these headphones is that they seem to instantly connect to bluetooth. It works wonderfully. I decided to buy this product and I love it! Ive tried multiple knob settings and the hum is just as loud. you just keep walking. No rough edges, the colours are clear and bright, I can?t fault them. I tried to have fixed, was going to cost $80. There is very little support in these slippers although the sole is soft. I regret buying them despite how nice they look. Also, the plug on the QC30 never seemed to fit quite right.