While the Bluetooth range of some devices can be up to 15 meters (or even more) as standard, the recommended optimal range for a Bluetooth stereo device is approximately half a meter in a direct line to your music device. This is especially true outdoors where the signal cannot use walls and ceilings to be contained.
This rule applies to any brand of Bluetooth stereo devices. In MIIEGO® headphones, the antenna is located on the right side of the earcup. Therefore, always make sure that your device is on the right side of your body when you are outdoors to achieve optimal connection! This will help avoid signal dropouts. Also, be aware that antennas on iPhones are located at the bottom of the phone.