We analyze the impact on the Madden-Julian Oscillation of an interactive mixed-layer ocean and cloud-radiative feedbacks associated with the deep moist convection. A simplified case is studied as a linear eigen-value problem, and compared to nonlinear simulations with the Quasi-equilibrium Tropical Circulation Model (QTCM1). Adding to the better-known mechanisms such as the evaporation-wind feedback, a mixed-layer ocean tends to damp the atmospheric moist Kelvin wave because the SST is lowered as enhanced evaporation takes heat out of ocean. Increased cloud cover in convective regions reduces solar radiation reaching the surface, thus adding further damping in these regions. More complexities come in the subsidence regions where enhanced solar rediation due to reduced cloud cover leads to warm SST, conducive to the development of convection. At extreme values in the parameter space of the linearized problem, instability can arise from the interactions of the moist Kelvin wave with ocean and clouds. The original moist-Kelvin wave speed is also modified by the interactive SST and cloud effects. The numerical model results partially support the analytical results, but at the same time suggest additional complexities.