The Beats Solo Pro is for the listener who's always on the move. Noise cancelling is surprisingly effective for a pair of on-ear headphones. Although the sound signature remains bass-heavy, as is emblematic of Beats, it rarely overpowers vocal reproduction.
1 
Have you tried resetting them?
Here’s a guide for that
https://support.apple.com/en-us/HT201118
由 HelloMacOS 完成的