During the growth of ZnTe by molecular beam epitaxy, we observed that, depending on the substrate temperature and flux ratio, the RHEED intensity oscillations can exhibit strong beats. Those beats are interpreted as a consequence of the coexistence, during growth, of c(2×2) and (2×1) surface reconstruction domains at the surface of (001)-ZnTe. The intensity beats superimposed on the regular oscillations are responsible for strong phase shift in the RHEED oscillations, which can be seriously misleading for an accurate determination of the growth rate.