The Xiaomi Buds 5 adopts a semi in-ear design, with an active adaptive noise cancellation function. The supported noise cancellation settings are Balance, Deep and Adaptive. You can switch between the Balance mode and the Deep mode manually according to your needs.
The adaptive noise cancellation is to switch between 2 noise cancellation modes automatically according to the noise level of the surroundings. It is defaulted in Deep mode to adjust the earbuds to the suitable ear pressure.
Note:
Concerning safety issues, it is not recommended that you wear earbuds when you need to pay attention to the environment like riding a bike or crossing the road.