diff --git a/src/StretcherChannelData.cpp b/src/StretcherChannelData.cpp
index 8378975..968feb5 100644
--- a/src/StretcherChannelData.cpp
+++ b/src/StretcherChannelData.cpp
@@ -104,6 +104,14 @@ RubberBandStretcher::Impl::ChannelData::construct(const std::set<size_t> &window
     for (size_t i = 0; i < initialWindowSize * oversample; ++i) {
         dblbuf[i] = 0.0;
     }
+
+    for (size_t i = 0; i < maxSize; ++i) {
+        accumulator[i] = 0.f;
+        windowAccumulator[i] = 0.f;
+    }
+
+    // Avoid dividing opening sample (which will be discarded anyway) by zero
+    windowAccumulator[0] = 1.f;
 }
 
 void
diff --git a/src/StretcherImpl.cpp b/src/StretcherImpl.cpp
index c175ab3..7ec7c16 100644
--- a/src/StretcherImpl.cpp
+++ b/src/StretcherImpl.cpp
@@ -934,9 +934,18 @@ RubberBandStretcher::Impl::calculateStretch()
 {
     Profiler profiler("RubberBandStretcher::Impl::calculateStretch");
 
+    size_t inputDuration = m_inputDuration;
+
+    if (!m_realtime && m_expectedInputDuration > 0) {
+        if (m_expectedInputDuration != inputDuration) {
+            std::cerr << "RubberBandStretcher: WARNING: Actual study() duration differs from duration set by setExpectedInputDuration (" << m_inputDuration << " vs " << m_expectedInputDuration << ", diff = " << (m_expectedInputDuration - m_inputDuration) << "), using the latter for calculation" << std::endl;
+            inputDuration = m_expectedInputDuration;
+        }
+    }
+
     std::vector<int> increments = m_stretchCalculator->calculate
         (getEffectiveRatio(),
-         m_inputDuration,
+         inputDuration,
          m_phaseResetDf,
          m_stretchDf);
 
diff --git a/src/StretcherProcess.cpp b/src/StretcherProcess.cpp
index 7c3f1e7..3f7d1fb 100644
--- a/src/StretcherProcess.cpp
+++ b/src/StretcherProcess.cpp
@@ -735,7 +735,7 @@ RubberBandStretcher::Impl::modifyChunk(size_t channel,
             bool inherit = false;
 
             if (laminar) {
-                if (distance >= mi) {
+                if (distance >= mi || i == count) {
                     inherit = false;
                 } else if (bandlimited && (i == bandhigh || i == bandlow)) {
                     inherit = false;
diff --git a/src/sysutils.cpp b/src/sysutils.cpp
index 1e6ef3a..af482e9 100644
--- a/src/sysutils.cpp
+++ b/src/sysutils.cpp
@@ -110,7 +110,7 @@ float *allocFloat(float *ptr, int count)
     void *allocated;
 #ifndef _WIN32
 #ifndef __APPLE__
-    if (!posix_memalign(&allocated, 16, count * sizeof(float)))
+    if (posix_memalign(&allocated, 16, count * sizeof(float)))
 #endif
 #endif
         allocated = malloc(count * sizeof(float));
@@ -134,7 +134,7 @@ double *allocDouble(double *ptr, int count)
     void *allocated;
 #ifndef _WIN32
 #ifndef __APPLE__
-    if (!posix_memalign(&allocated, 16, count * sizeof(double)))
+    if (posix_memalign(&allocated, 16, count * sizeof(double)))
 #endif
 #endif
         allocated = malloc(count * sizeof(double));