The features of a cylindrical shear-axial wave scattering by a circular cavity in piezoelectric crystal of 6(4)-class of symmetry are discussed. It is shown that the basic integral characteristics of scattering—scattering indicatrix and total cross-section scattering have large changes with approach of a linear shear-axial wave source to cavity boundary. The small-scale oscillations in spectra of scattering are caused by the interference contribution of waves circulating on a boundary as they are capable of effective capture by concave metallized boundary of a cavity.