diff --git a/src/testing.c b/src/testing.c
index 3340123..572dcdc 100644
--- a/src/testing.c
+++ b/src/testing.c
@@ -1393,6 +1393,11 @@
 	repeated_click = (int)dict_get_number(args, (char_u *)"multiclick");
 	mods = (int)dict_get_number(args, (char_u *)"modifiers");
 
+	// Reset the scroll values to known values.
+	// XXX: Remove this when/if the scroll step is made configurable.
+	mouse_set_hor_scroll_step(6);
+	mouse_set_vert_scroll_step(3);
+
 	gui_send_mouse_event(button, TEXT_X(col - 1), TEXT_Y(row - 1),
 							repeated_click, mods);
     }