The MIC, ECHO & music volume, its starting & limit the volume setting function;

麦克风音量，ECHO音量和音乐主音量起始音量和限制音量设定功能；

youdao

It sounded like they cut Rachel's mic off or at least turned the volume down so that Steve Jones could do his thing.

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And while they were impressed with the 30 fps, 1, 280-by-1, 024 (interpolated, of course) video, they found that the audio quality from the built-in mic left a lot to be desired, having to crank up the volume in order to hear each other clearly, resulting in some nasty feedback.

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