The ornamental design for a racquetvibrationdampner, as shown and described.
FIG. 1 is a front view of the racquet vibration dampner;
FIG. 2 is a side view of the racquet vibration dampner of FIG. 1, the opposing sides are symmetric;
FIG. 3 is a perspective view of the racquet vibration dampner of FIG. 1; and,
FIG. 4 is a front view of the racquet vibration dampner of FIG. 1 illustrated in the context of a tennis racquet. The environment shown in broken lines in FIG. 4 is for illustrative purposes only and forms no part of the claimed design.