diff --git a/tests/gsa/ls2003a.mod b/tests/gsa/ls2003a.mod
index 2f0dc73f2..b096acbc2 100644
--- a/tests/gsa/ls2003a.mod
+++ b/tests/gsa/ls2003a.mod
@@ -97,13 +97,16 @@ y_obs,R_obs(@{ilag}), -; //[ccf]
 y_obs,pie_obs(@{ilag}), -; //[ccf]
 @#endfor
 end;
+
+options_.prior_mc=5000;
+
 prior simulate;
 prior moments(distribution);
 
 if isoctave()
-  dynare_sensitivity(prior_range=0, nodisplay, graph_format=(eps));
+  dynare_sensitivity(prior_range=0, nodisplay, graph_format=(eps),Nsam=1024);
 else
-  dynare_sensitivity(prior_range=0, nodisplay, graph_format=(fig));
+  dynare_sensitivity(prior_range=0, nodisplay, graph_format=(fig),Nsam=1024);
 end
 
 /*