As a dod user who powers several of them at once with a daisy-chain, I can confidently tell you (and agree with the others) that is a power issue. Make sure any exposed power jacks you are not using are either covered in electrical tape or some other method. If they are shorting against something they will do exactly what your describing and probably make some awful noise will doing it. If it turns appears that you have the jacks all covered and the problem still exists, check the connection between the daisychain itself and the power source. I'm using an ooooold power supply with a new daisychain and 1/4 of the possible outputs on the power source is shorted out. I hope you figure it out.

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