You may have noticed that Live’s Compressor sometimes produces an audible clicking sound in the signal when the sidechain is activated.

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There are two easy ways around this.

Turn up the Knee:

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This applies the compression more gradually and often stops the clicking.

Or, switch Mode to FF1:

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FF1 tends to be the most lo-fi mode of Compressor and is often used when you want a more obvious compression effect. With the sidechain activated, it can produce surprisingly great sounding results with lots of punch.