Headphone Jack Recording
As of 10.14.6, it is not possible to record audio through the headphone jack with anything but the Apple EarPods microphone, yet this article shows an option in sound settings that lets you record, presumeably through the output conductors of the jack, allowing for stereo recording, in contrast to the mono recording of the EarPods microphone. Judging by the date of the article, this seems to be from some version of 10.6. When and why was this feature removed?
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