The paper focuses on some of the signals that interfere with the proper functioning of hydraulic valves. Special attention has been given to mechanical vibration regarding the hydraulic manifold and lines. Experimental tests were carried out on a designed hydraulic bench using a hydraulic simulator as a source of harmonic vibrations acting on a hydraulic manifold. Changes in the pressure pulsation spectrum of a hydraulic system with a vibrating hydraulic manifold were analyzed. In the spectrum of pressure pulsations in a hydraulic system with a vibrating manifold, harmonic components appear with frequency values corresponding to the frequencies of external mechanical vibrations generated by the hydraulic simulator. In hydraulic lines, it leads to flexural vibration of the line, and in other valves, to vibration of their bodies. The amplitude-frequency spectrum of the speed of the hydraulic cylinder, whose operation was controlled by a vibrating proportional valve, was also analyzed. To reduce the vibration of the valve body, it was proposed to use a vibration isolator with fixed, linear characteristics. The selection of the parameters of the vibration isolator should be carried out so that its effectiveness is greatest in the vicinity of the resonance frequency of the valve spool or control element.