diff --git a/pipeline/stage03_trigger_detection/scripts/hilbert_phase.py b/pipeline/stage03_trigger_detection/scripts/hilbert_phase.py
index a1a31a135..06e170da3 100644
--- a/pipeline/stage03_trigger_detection/scripts/hilbert_phase.py
+++ b/pipeline/stage03_trigger_detection/scripts/hilbert_phase.py
@@ -64,12 +64,12 @@ def _detect_phase_crossings(phase):
     sort_idx = np.argsort(up_transitions)
 
     evt = neo.Event(times=up_transitions[sort_idx]*asig.times.units,
-                     labels=['UP'] * len(up_transitions),
-                     name='Transitions',
-                     array_annotations={'channels':channels[sort_idx]},
-                     hilbert_transition_phase=transition_phase,
-                     description='Transitions from down to up states. '\
-                                +'annotated with the channel id ("channels").')
+                    labels=['UP'] * len(up_transitions),
+                    name='Transitions',
+                    array_annotations={'channels':channels[sort_idx]},
+                    hilbert_transition_phase=transition_phase,
+                    description='Transitions from down to up states. '\
+                               +'annotated with the channel id ("channels").')
 
     for key in asig.array_annotations.keys():
         evt_ann = {key : asig.array_annotations[key][channels[sort_idx]]}
diff --git a/pipeline/stage04_wave_detection/scripts/trigger_clustering.py b/pipeline/stage04_wave_detection/scripts/trigger_clustering.py
index 3243258b5..4db9b0264 100644
--- a/pipeline/stage04_wave_detection/scripts/trigger_clustering.py
+++ b/pipeline/stage04_wave_detection/scripts/trigger_clustering.py
@@ -32,7 +32,7 @@ def cluster_triggers(event, metric, neighbour_distance, min_samples,
     wave_idx = up_idx[cluster_idx]
 
     evt = neo.Event(times=event.times[wave_idx],
-                    labels=clustering.labels_[cluster_idx],
+                    labels=clustering.labels_[cluster_idx].astype(str),
                     name='Wavefronts',
                     array_annotations={'channels':event.array_annotations['channels'][wave_idx],
                                        'x_coords':triggers[:,0][cluster_idx],