diff --git a/src/vegas_mode/render_pipeline.py b/src/vegas_mode/render_pipeline.py
index a2fddcc8..d1af0c79 100644
--- a/src/vegas_mode/render_pipeline.py
+++ b/src/vegas_mode/render_pipeline.py
@@ -102,6 +102,8 @@ class RenderPipeline:
         self._cycle_complete = False
         self._segments_in_scroll: List[str] = []  # Plugin IDs in current scroll
 
+        # The sub-pixel path's pacing; the crisp path solves its own (frame_interval).
+        self._frame_interval = config.get_frame_interval()
         self._cycle_start_time = 0.0
 
         # Statistics
@@ -883,6 +885,7 @@ class RenderPipeline:
         """
         old_fps = self.config.target_fps
         self.config = new_config
+        self._frame_interval = new_config.get_frame_interval()
 
         # Reconfigure scroll helper
         self._configure_scroll_helper()
diff --git a/test/test_vegas_coordinator_iteration.py b/test/test_vegas_coordinator_iteration.py
index 329b36fa..954c33b7 100644
--- a/test/test_vegas_coordinator_iteration.py
+++ b/test/test_vegas_coordinator_iteration.py
@@ -21,6 +21,9 @@ def _coordinator(plugins):
     coord.vegas_config = VegasModeConfig.from_config({'display': {'vegas_scroll': {
         'enabled': True, 'max_cycle_duration': 0}}})
     coord.render_pipeline = MagicMock()
+    # The loop paces itself from these (#628); a MagicMock can't be compared.
+    coord.render_pipeline.frame_interval = 0.0
+    coord.render_pipeline.target_fps = 90
     coord.stream_manager = MagicMock()
     coord.display_manager = MagicMock()
     coord.plugin_manager = SimpleNamespace(plugins=plugins, get_plugin=plugins.get)