Twilio Client has been updated to provide more control over WebRTC primitives, particularly getUserMedia, allowing developers to manually adjust parameters such as audio gain control. This feature is useful in environments where device-specific issues occur and can be used to work around problems like the Windows auto-gain control issue mentioned, by passing specific settings directly to the underlying call to getUserMedia. The new `audioConstraints` parameter allows developers to enable or disable features like AGC, and can also be used to programmatically choose a specific audio device.