Initially, the M3 would not connect to my Bluetooth headphones (QCY Q29). This turned out to be because my headphones were Bluetooth v4.1, whereas the M3 only supports up to Bluetooth v4.0 out of the box. However, email support were extremely fast and helpful, replying within a day, and immediately sent me updated firmware (with very thorough …
https://www.amazon.com/Victure-Bluetooth-Pedometer-Earphones-Expandable/dp/B07BF86RK1

