The model problem of spreading waves in a viscoelastic medium with spherical cavity catised by dynamical load applied to the surface of sphere is considered in this article. The solution is carried out the compliance with the principle of elastic and viscoelastic problems. For a qualitative analysis we use the asymptotic expansion for the integrand obtained for the radial stress. Some examples of calculations of the action impulse and a series of random impulses are represented. From the results one can see that tha nature of spreading of disturbances can vary greatly depending on the applied load.