Have you tried modifying the volume of the headroom?
Follow this route: preferences - mixer - output level - headroom
Something similar happened to me with the DDJ 1000 and after several headroom configurations in -9db it is how I better adjust the level of the FX and Pad FX.
Test also has edit parameters of the effects in the padFX, some sound very loud and modifying the parameter you will more or less adjust it.
