Using 4 independent switches to select different input or output, fully isolated independent circuit, maker sure that each signal is not affected by the other three channels. To solve the common ground noise caused by the connection of multiple audio sources. Preset 4 blank squares for you to write names of different audio equippments connected to MC104 PRO, more convenient for you to compare your lovely HiFi audio device and no need to check which machines are connected one by one.
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