To reset your Aftershokz Aeropex headphones, follow these steps: 1. Power off the headphones: Press and hold the multifunction button (the raised button near the charging port) for 3-5 seconds until you hear the headphones say "Power off" or until the LED indicator turns off. 2. Clear pairing history: Start with the headphones turned off. Press and hold the "+" (volume up) and "-" (volume down) buttons simultaneously for about 5 seconds until you hear two beeps. This will clear the pairing history on the headphones. 3. Factory reset: With the headphones still turned off, press and hold the multifunction button for about 10-15 seconds. The LED indicator will flash red and blue, and you'll hear the headphones say "Welcome to Aftershokz" followed by "Pairing." This indicates that the headphones have been reset and are now in pairing mode. 4. Reconnect to your device: Turn on Bluetooth on your device, search for available devices, and select "Aftershokz Aeropex" from the list. Follow any on-screen instructions to complete the pairing process. Keep in mind that resetting the headphones will clear their pairing history, so you'll need to re-pair them with your devices afterward.