It is shown for an infinitely long waveguide - first in the form of a two-dimensional and then a three-dimensional channel - filled with an ideal compressible liquid with a free surface, that there can exist standing waves as well as traveling waves localized in the region of a dynamic submerged object - a massive die. The appearance of such waves is due to the presence of a mixed spectrum of characteristic frequencies of oscillation. In addition to the continuous spectrum, a point (discrete) spectrum distributed along the axis of the continuous spectrum is also present. A relation is found between the geometric parameters of the channel and the massive die for which this spectrum exists.