Connect the AVENTHO 300 to your mobile phone via Bluetooth.
Download the beyerdynamic app and install it on your mobile phone. After opening the app, you can connect the AVENTHO 300 to the app via "Add product".
The beyerdynamic app checks whether an update is available for your AVENTHO 300. If the message "Update available" appears, follow the instructions in the app to install the update on the headphones. This requires a mobile data connection.