The input source is set to the microphone (mic).

输入源被设置为麦克风(mic)。

youdao

My test unit also came with an odd little add-on microphone poking out from the bottom, even though it had a built-in mic at the top.

我测试的这台电脑还有一个古怪的外置麦克风，从机器底部伸出来，而其实电脑顶部已经有了一个内置麦克风。

youdao

Mic interface and microphone connections, for chatting or recording.

MIC接口与麦克风连接，用于聊天或者录音。

youdao

"Just kind of uh, just stepped off the cliff and said 'okay where's that microphone.' Made a short couple of comments and then put the mic down and dropped down on one knee and.

VOA: standard.2010.02.27

There should be a microphone -- wait till the mic comes so everybody can hear you.

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This means you can run your own mic solution if the internal microphone isn't up to your standards (and there's a good chance it won't be).

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Additionally, videographers have the ability to capture audio with the onboard microphone or record stereo audio externally using the mic input.

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