Loud creaking noise with every tiny movement = straight back in the box and back to Amazon for a refund.
See the attached video for an example of what I'm talking about.
Come on guys, this is basic headphone engineering. If I can't hear the music over the noise the plastic is making there's no point.
Also, the active noise cancellation actually adds noise. Anytime there's a loud sound or drastic change in the tonal quality of some noise that is being filtered there is, for lack of a better term, a loud farting noise in the left earphone.
Which doesn't help the fact that the noise cancellation can't keep up with any noise because the latch on noise changes is too slow to keep up with changes in sound in the environment. This is a feature of most bad noise canceling headphones and results in a constant wah-wah effect as the noise around you gets louder and softer.
EDIT 7/10/2019: After I returned this product I recieved a barrage of emails, text messages and phone calls from a company called Amazon Review Services. I do not know how they got my personal email address and phone number, but this makes me very uncomfortable. Not only will I never order from this merchant again, I recommend that everyone else avoid them as well.