diff --git a/src/clickTrainDetector/clickTrainAlgorithms/mht/MHTClickTrainAlgorithm.java b/src/clickTrainDetector/clickTrainAlgorithms/mht/MHTClickTrainAlgorithm.java
index 66fdabe3..7f50025e 100644
--- a/src/clickTrainDetector/clickTrainAlgorithms/mht/MHTClickTrainAlgorithm.java
+++ b/src/clickTrainDetector/clickTrainAlgorithms/mht/MHTClickTrainAlgorithm.java
@@ -354,6 +354,7 @@ public class MHTClickTrainAlgorithm implements ClickTrainAlgorithm, PamSettings
 		TrackBitSet trackBitSet;
 		TrackDataUnits trackUnits;
 		if (nTracks>0) Debug.out.println("-------------------Grab Done Trains---------------");
+		try {
 		for (int i =0; i<nTracks; i++) {
 			trackBitSet=mhtKernal.getConfirmedTrack(i);
 			Debug.out.println("MHTAlgorithm: Confirmed Track Grab: No. " + MHTKernel.getTrueBitCount(trackBitSet.trackBitSet)  + " flag: " + trackBitSet.flag + "  chi2: " +trackBitSet.chi2Track.getChi2()); 
@@ -379,6 +380,10 @@ public class MHTClickTrainAlgorithm implements ClickTrainAlgorithm, PamSettings
 			trackCount++;
 			saveClickTrain(trackUnits, trackBitSet.chi2Track.getMHTChi2Info());
 		}
+		}
+		catch (Exception e) {
+			System.out.printf("*******  MHTClickTrainAlgorithm Exception %s in grabDoneTrains: %s\n", e.getClass().getSimpleName(), e.getMessage());
+		}
 		
 		if (nTracks>0) Debug.out.println("-------------------------------------------------");
 
diff --git a/src/clickTrainDetector/clickTrainAlgorithms/mht/MHTKernel.java b/src/clickTrainDetector/clickTrainAlgorithms/mht/MHTKernel.java
index 3a4fb0ee..4fa9cdfb 100644
--- a/src/clickTrainDetector/clickTrainAlgorithms/mht/MHTKernel.java
+++ b/src/clickTrainDetector/clickTrainAlgorithms/mht/MHTKernel.java
@@ -3,6 +3,7 @@ package clickTrainDetector.clickTrainAlgorithms.mht;
 import java.util.ArrayList;
 import java.util.BitSet;
 import java.util.Collections;
+import java.util.Comparator;
 
 import PamUtils.PamArrayUtils;
 import PamguardMVC.debug.Debug;
@@ -286,6 +287,7 @@ public class MHTKernel<T> {
 			MHTChi2<T> mhtChi2;
 			int index; 
 			synchronized(trackSynchronisation) {
+				try {
 				for (int i=0; i<possibleTracks.size(); i++) {
 
 					currentBitSet=possibleTracks.get(i).trackBitSet;
@@ -313,6 +315,10 @@ public class MHTKernel<T> {
 					//added the cloned bitset to not mess up references 
 					newPossibilities.add(new TrackBitSet(currentBitSet, mhtChi2)); 
 				}
+				}
+				catch (Exception e) {
+					System.out.printf("*******  MHTKernel Exception %s in growProbMatrix: %s\n", e.getClass().getSimpleName(), e.getMessage());
+				}
 			}
 		}
 
@@ -348,10 +354,21 @@ public class MHTKernel<T> {
 			//first sort the tracks by increasing chi2 values. 
 			//sort the possible tracks by chi2 values
 			//now sort the chi2 values so they correspond to the track list.  
-			Collections.sort(newPossibleTracks, (left, right)->{
-				//Note- this is definitely in the correct order
-				return Double.compare(left.chi2Track.getChi2(), right.chi2Track.getChi2());
-			});		
+//			Collections.sort(newPossibleTracks, (left, right)->{
+//				//Note- this is definitely in the correct order
+//				return Double.compare(left.chi2Track.getChi2(), right.chi2Track.getChi2());
+//			});		
+			try {
+			Collections.sort(newPossibleTracks, new Comparator<TrackBitSet>() {
+				@Override
+				public int compare(TrackBitSet left, TrackBitSet right) {
+					return Double.compare(left.chi2Track.getChi2(), right.chi2Track.getChi2());
+				}
+			});
+			}
+			catch (Exception e) {
+				System.out.printf("*******  MHTKernel Exception %s in pruneProbMatrix: %s\n", e.getClass().getSimpleName(), e.getMessage());
+			}
 
 			//			for (int i=0; i<newPossibleTracks.size(); i++) {
 			//				System.out.print("Possibility chi2: " + i +  "  " + String.format("%.3f", newPossibleTracks.get(i).chi2Track.getChi2()));