diff --git a/libwfr/src/MultiStreamOscilloscope.cpp b/libwfr/src/MultiStreamOscilloscope.cpp
index 6828f21..e339bd1 100644
--- a/libwfr/src/MultiStreamOscilloscope.cpp
+++ b/libwfr/src/MultiStreamOscilloscope.cpp
@@ -16,13 +16,14 @@ MultiStreamOscilloscope::MultiStreamOscilloscope() {
     mFIFOBlockCnt = 0;
     mCaptureLength = 0;
     mPreTriggerSamples = 0;
+    mDrawMarginSamples = DRAW_WINDOW_MARGIN_DEF;
 }
 
 void MultiStreamOscilloscope::setup(const std::vector<in_addr_t> &nodes, const AcquisitionFormat &acqFmt) {
     MultiStreamProcessor::setup(nodes, acqFmt);
 
     // calculate buffer parameters
-    mCaptureLength = ceil(mCapturePeriod_ns / 1E+09 * acqFmt.sampling_rate_Hz); // calculate draw window period in samples
+    mCaptureLength = ceil(mCapturePeriod_ns / 1E+09 * acqFmt.sampling_rate_Hz) + 2 * mDrawMarginSamples; // calculate draw window period in samples
     mFIFOBlockCnt = 10 * ceil(mCaptureLength / acqFmt.mch_samples_per_packet); // TODO magic...
 
     // setup channel buffers
@@ -215,9 +216,6 @@ std::vector<std::vector<MultiStreamOscilloscope::SamplePoint>> MultiStreamOscill
         mTrigState.samplesReady = false;
         return mCaptureBuffers;
     } else {
-        if (mTrigState.autoTrigger) {
-            mTrigState.trigd = true; // trigger if auto-trigger is enabled
-        }
         return {};
     }
 }
diff --git a/libwfr/src/MultiStreamOscilloscope.h b/libwfr/src/MultiStreamOscilloscope.h
index 05da284..762fcdb 100644
--- a/libwfr/src/MultiStreamOscilloscope.h
+++ b/libwfr/src/MultiStreamOscilloscope.h
@@ -17,6 +17,7 @@ public:
     static constexpr size_t DRAW_WINDOW_PERIOD_NS_DEF = 50E+06; // default window length (50ms)
     static constexpr double VOLT_PER_BIN_DEF = 42.80E-06; // default vertical resolution
     static constexpr size_t TRIGGER_POS_PERCENT_DEF = 50; // trigger position is defaulted to the screen center
+    static constexpr ssize_t DRAW_WINDOW_MARGIN_DEF = 10; // size of margin on each end of the sample capture buffer
 public:
     struct SamplePoint {
         int64_t t; // time
@@ -46,6 +47,7 @@ public: // graphical displaying related things
     size_t mTriggerPosition_percent; // trigger position on the screen
     size_t mTriggerProbeBlock_idx; // index of block on which trigger will run
     size_t mPreTriggerSamples; // samples displayed before the trigger point
+    ssize_t mDrawMarginSamples; // margin to avoid artifacts on the screen's edge
     size_t mCapturePeriod_ns; // (drawing window) screen period
 public:
     std::shared_ptr<TriggerSettings> trigger; // trigger settings
diff --git a/python/runtime/main.py b/python/runtime/main.py
index 5df09cb..1f29381 100644
--- a/python/runtime/main.py
+++ b/python/runtime/main.py
@@ -1,6 +1,8 @@
 import time
 import sys
 
+import matplotlib.ticker
+
 sys.path.extend(['../module'])
 
 import pywfs
@@ -11,8 +13,9 @@ from matplotlib import pyplot as plt
 from matplotlib import animation as anim
 import time
 
-LOCAL_ADDR = "192.168.1.204"
-nodes = [ "192.168.1.180" ]
+#LOCAL_ADDR = "192.168.1.204"
+LOCAL_ADDR = "10.42.0.1"
+nodes = [ "10.42.0.106" ]
 
 # ---------- CONNECT TO AND PREPARE SAMPLING SYSTEM -----------
 
@@ -44,7 +47,7 @@ osc = pywfs.MultiStreamOscilloscope.create()
 
 # create a slope trigger
 edge_trigger = pywfs.EdgeTrigger()
-edge_trigger.level = 0.1
+edge_trigger.level = 0.5
 edge_trigger.edge = pywfs.FALLING
 #edge_trigger.ch = 0 + index
 edge_trigger.ch = 0
@@ -123,6 +126,8 @@ def init():
 
 fig, ax = plt.subplots()
 lines = list()
+ax.xaxis.set_major_formatter(matplotlib.ticker.EngFormatter(unit='s'))
+ax.yaxis.set_major_formatter(matplotlib.ticker.EngFormatter(unit='V'))
 
 # trigger mark
 screen_period = osc.getScreenPeriod() * 1E-09
@@ -131,10 +136,11 @@ trig_t = [-trig_mark_halflen * screen_period, trig_mark_halflen * screen_period
 trig_y = [ edge_trigger.level, edge_trigger.level ]
 
 for k in range(0, ch_n):
-    lines.append(ax.plot([], [], lw=2))
+    lines.append(ax.plot([], [], label="CH" + str(k), lw=2))
     t, y = list(), list()
 
 ax.plot(trig_t, trig_y, color = 'r')
+ax.legend()
 
 def run(data):
     T, Y = data