Hi Marcel, On 11/2/21 9:43 AM, Marcel Holtmann wrote: > you can use btmgmt tool from bluez.git to force Secure Connections off. I am not sure if that sticks when starting bluetoothd, but then you need to hack it out there. Thank you! This works. I had to run 'btmgmt sc off' after starting bluetoothd, before 'power on', but then I was able to pair with my device. When paired MIDI over Bluetooth is working properly. Even after I re-enable SC the connection with the already-paired device works. I think I can work with that. > I am really not sure how your device can be a qualified Bluetooth device and fail here. The handling of the flags has actually proper test cases to ensure that this does’t happen. That would not be a first time when a device is compatible with the standard it is advertised with. Especially that for this one this is extra feature hardly anyone uses and the manufacturer does not even support their own software properly (the Android app just doesn't work) and usually the USB interface would be rather used than BT, anyway. What is interesting this amplifier has two different BT adapters. It can function as a 'bluetooth speaker' and this seems to be working without any issue. It is the 'regular Bluetooth', not LE. This one feature would be probably enough to call this Bluetooth device. The other function is amplifier remote control via MIDI over Bluetooth. This seems to be a separate BLE interface and works as I described. It does not even have any special 'pairing mode' (the 'speaker' function requires pressing a button on the device) or pairing verification, so anyone can pair with the amplifier at any time (unless already someone else uses the BLE interface) and change its settings. It would be quite an interesting attack if anyone used those devices on stage. Using SC or not probably does not matter at this point at all. Greets, Jacek
