* - playback device sample rate
* - PlaybackChannels
* - playback device channel count
+ * - PlaybackChannel#
+ * - describe index of the logical channel in the PCM stream
+ * - e.g. "PlaybackChannel0 2" - logical channel 0 is third channel in the PCM stream
+ * - PlaybackChannelPos#
+ * - describe sound position of the logical channel (ALSA chmap names)
+ * - e.g. "PlaybackChannel0 FR" - logical channel 0 is at front left
* - PlaybackCTL
* - playback control device name
* - PlaybackVolume
* - capture device sample rate
* - CaptureChannels
* - capture device channel count
+ * - CaptureChannel#
+ * - describe index of the logical channel in the PCM stream
+ * - e.g. "CaptureChannel0 2" - logical channel 0 is third channel in the PCM stream
+ * - CaptureChannelPos#
+ * - describe sound position of the logical channel (ALSA chmap names)
+ * - e.g. "CaptureChannel0 FR" - logical channel 0 is at front left
* - CaptureCTL
* - capture control device name
* - CaptureVolume