OptionalautoOptionalchannelthe channel count or range of channel counts which are acceptable and/or required
OptionaldeviceA ConstrainDOMString object specifying a device ID or an array of device IDs which are acceptable and/or required.
Optionalechowhether or not echo cancellation is preferred and/or required
Optionallatencythe latency or range of latencies which are acceptable and/or required.
Optionalnoisewhether noise suppression is preferred and/or required.
Optionalprocessorinitialize the track with a given processor
Optionalsamplethe sample rate or range of sample rates which are acceptable and/or required.
Optionalsamplesample size or range of sample sizes which are acceptable and/or required.
Optional Experimentalvoicea stronger version of 'noiseSuppression', browser support is not widespread yet. If this is set (and supported) the value for 'noiseSuppression' will be ignored
specifies whether automatic gain control is preferred and/or required