A combined Fermi-Davydov resonance in solid molecular solutions is considered. It is shown that migration of the energy of vibrational excitation can lead to an abnormal redistribution of intensities of the components of Fermi-doublet when higher order harmonics are dominant. The concentrational dependence of the ratio of the intensities of doublet components is investigated. At a certain value of the concentration, determined by parameters of the solvent and the dissolved substance, a sharp increase in the intensity of one of the doublet components can be observed. The basic conclusions of the theory are in agreement with the experiment.