diff --git a/gui_client.py b/gui_client.py
index c73475b..0a371c8 100644
--- a/gui_client.py
+++ b/gui_client.py
@@ -615,6 +615,7 @@ class PlotTab(QWidget):
             if pi.legend:
                 pi.legend.clear()
 
+            x_min = None
             for j, key in enumerate(self._traces[i]):
                 if key not in self._series:
                     continue
@@ -622,6 +623,7 @@ class PlotTab(QWidget):
                 if not series:
                     continue
                 times, values = zip(*series)
+                x_min = times[0] if x_min is None else min(x_min, times[0])
                 label = f"{_trace_label(key)} [{self._units.get(key, '')}]"
                 pw.plot(
                     list(times), list(values),
@@ -629,7 +631,7 @@ class PlotTab(QWidget):
                     name=label,
                 )
 
-            pw.setXRange(cutoff, now, padding=0.02)
+            pw.setXRange(x_min if x_min is not None else cutoff, now, padding=0.02)
 
     # ── cursor tracing ────────────────────────────────────────────────────────