Small transient stress perturbations are prone to trigger (micro)seismicity. In the Earth’s crust, these stress perturbations can be caused by various sources such as the passage of seismic waves, forcing by tides, or hydrological seasonal loads. A better understanding of the dynamic of earthquake triggering by stress perturbations is essential in order to improve our understanding of earthquake physics and our consideration of seismic hazard. Here, we study an experimental sandstone-gouge-filled fault system undergoing combined far field loading and periodic stress perturbations (of variable amplitude and frequency) at crustal pressure conditions. Microseismicity — in the form of acoustic emissions (AE) — strains, and stresses, are continuously recorded in order to study the response of microseismicity as a function of loading rate, amplitude and frequency of a periodic stress perturbation. The observed AE distributions do not follow the predictions of a Coulomb failure model taking into account both constant loading and oscillation-induced strain rates. A susceptibility of the system’s AE response to confinement pressure amplitude is estimated, which showcases a linear relation between confinement pressure amplitude and the AE response amplitude, observations which agree with recent higher frequency experimental results on dynamic triggering. The magnitude-frequency distribution of AEs is also computed. Oscillations in Gutenberg-Richter b-value are observed in experiment catalogues but are not quantified. Our experiments may help complement our understanding of the influence of low inertia stress phenomena on the distribution of seismicity, such as observations of dynamic triggering and seismicity modulation by solid earth tides or seasonal loading.