B, no noise tracking method: input power amplifier (RCA), released the CD signal output, check whether there is noise.

没有噪音的跟踪方法：将功放的输入(rca)恢复，解除CD机的讯号输出，检查是否有噪音。

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In an amplifier, a DVD, or a CD player, the sound signal consists of electrons, which are processed and moved quickly and precisely between the components with almost no loss of important information.

在扩音器内部，DVD或CD播放机，声音信号组成电子场，在元素之间快速正确的移动前进，不会漏掉重要的资讯。

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Amplifier and CD: foot nails, pads, double units.

功放及CD：脚钉，垫板，双层台。

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