diff --git a/MUNGA/MOVER.cpp b/MUNGA/MOVER.cpp
index 5f260e6..7e2f809 100644
--- a/MUNGA/MOVER.cpp
+++ b/MUNGA/MOVER.cpp
@@ -47,6 +47,14 @@ static const Scalar	kMinimumPredictedInterval	= 0.010f;
 //
 static const Scalar	kMaximumPredictedInterval	= 0.25f;
 
+//
+// A gap this long is a stall, not jitter - six times the observed rate.
+// A gap this short cannot be a sender keeping to 30ms, so it is a packet
+// that was already waiting when we finally got round to reading it.
+//
+static const Scalar	kLongGapThreshold			= 0.200f;
+static const Scalar	kQueuedGapThreshold			= 0.005f;
+
 //~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 //
 // RP412NETPREDICT=0 restores the original single-sample prediction, so the
@@ -745,7 +753,21 @@ void
 							<< "m, predicting " << predictedInterval
 							<< "s worst miss " << worst_error << "s\n"
 							<< std::flush;
+
+						DEBUG_STREAM << "CamLog: replicant arrivals - widest gap "
+							<< widestGap << "s, " << longGapCount
+							<< " long, " << queuedGapCount
+							<< " queued ("
+							<< ((longGapCount > 0 && queuedGapCount > 0)
+									? "our loop stalled"
+									: (longGapCount > 0
+										? "sender went quiet"
+										: "clean"))
+							<< ")\n" << std::flush;
 					}
+					widestGap = 0.0f;
+					longGapCount = 0;
+					queuedGapCount = 0;
 					next_say = ((Scalar) Now()) + 5.0f;
 					steps = 0;
 					spikes = 0;
@@ -1025,6 +1047,14 @@ void
 					}
 					predictedInterval = predicted;
 
+					//
+					// Arrival statistics, for telling a quiet sender from
+					// our own stalled loop. See the members.
+					//
+					if (diff > widestGap)			{ widestGap = diff; }
+					if (diff > kLongGapThreshold)	{ longGapCount++; }
+					if (diff < kQueuedGapThreshold)	{ queuedGapCount++; }
+
 					nextUpdate += predicted;
 				}
 				else
@@ -2061,6 +2091,9 @@ Mover::Mover(
 	ResetUpdateIntervals();
 	predictedInterval = 0.0f;
 	predictionError = 0.0f;
+	widestGap = 0.0f;
+	longGapCount = 0;
+	queuedGapCount = 0;
 
 	normalizeCount = 0;
 	if (IsInitialStasis())
diff --git a/MUNGA/MOVER.h b/MUNGA/MOVER.h
index d193c80..53cb685 100644
--- a/MUNGA/MOVER.h
+++ b/MUNGA/MOVER.h
@@ -311,6 +311,19 @@ protected:
 		predictedInterval,
 		predictionError;
 
+	//
+	// Arrival statistics for the window a trace reports over. A long gap
+	// followed by normal gaps means the sender went quiet; a long gap
+	// followed by a burst of near-zero ones means OUR loop stalled and the
+	// packets queued up behind it. The two look identical from inside the
+	// dead reckoner and want opposite fixes.
+	//
+	Scalar
+		widestGap;
+	int
+		longGapCount,
+		queuedGapCount;
+
 	Scalar
 		PredictUpdateInterval(Scalar latest);
 	void