On the Bose Quiet Comfort Ultra 2 I've found you can disable voice prompts for "Connections & Calls" and "Battery Level on Startup" but not for everything e.g. "USB Audio" and "Bluetooth Audio" will play each time you switch the source.
On the Bose Quiet Comfort Ultra 2 I've found you can disable voice prompts for "Connections & Calls" and "Battery Level on Startup" but not for everything e.g. "USB Audio" and "Bluetooth Audio" will play each time you switch the source.