The safest and most reliable way to obtain the DDJ-400 skin is through the official Virtual DJ extension library.
Your DDJ-400 has eight pads per deck with four modes: Hot Cue, Pad FX, Beat Loop, and Sampler. A quality repack will visually display which mode you are in. When you press "Pad FX" on your controller, the on-screen pads should instantly change to FX names like "Flanger," "Delay," or "Reverb." pioneer ddj400 virtual dj skin download repack