Stellar acoustic oscillations are affected by magnetic activity, however it is unclear how a single starspot would affect the power spectrum of oscillations. Since the starspot rotates with the star, it causes a perturbation that is unsteady in the observer’s frame. Each (n, l) multiplet appears as (2l + 1) 2 blended peaks in the power spectrum, whose amplitudes depend on the star’s inclination and on the latitude of the starspot. We simulate example power spectra using both perturbation theory and numerical simulations.