diff --git a/src/audio.c b/src/audio.c
index 71c47e0..d7111e2 100644
--- a/src/audio.c
+++ b/src/audio.c
@@ -243,6 +243,14 @@ void PlaySelectedRegion(void)
     float* regionSamples = BuildSelectionAudio(&numSamples);
     if (!regionSamples) return;
 
+    // Snapshot what we're about to play so the playhead tracks THIS region even
+    // if the user moves the selection mid-playback. Duration comes from the
+    // buffer we actually built, not from app.signal.duration.
+    app.playSelStart = app.sel.timeStart;
+    app.playSelEnd   = app.sel.timeEnd;
+    app.playDuration = (app.signal.sampleRate > 0)
+                     ? (float)numSamples / (float)app.signal.sampleRate : 0.0f;
+
     EnsureAudioDevice();  // opened on demand; released again once playback ends
     if (AudioPlaybackSound.frameCount != 0) UnloadSound(AudioPlaybackSound);
 
diff --git a/src/render.c b/src/render.c
index 22e382b..6fb5988 100644
--- a/src/render.c
+++ b/src/render.c
@@ -1685,7 +1685,8 @@ void DrawPlayhead(Rectangle bounds)
 {
     if (!app.isPlaying || app.playheadT < 0.0f || app.playheadT > 1.0f) return;
 
-    float timePos = app.sel.timeStart + app.playheadT * (app.sel.timeEnd - app.sel.timeStart);
+    // Against the snapshot of the playing region, not the live selection.
+    float timePos = app.playSelStart + app.playheadT * (app.playSelEnd - app.playSelStart);
     float viewWidth = app.view.end - app.view.start;
     float t = (timePos - app.view.start) / viewWidth;
     float x = bounds.x + t * bounds.width;
diff --git a/src/spectrogram.c b/src/spectrogram.c
index ef872e3..337e82e 100644
--- a/src/spectrogram.c
+++ b/src/spectrogram.c
@@ -945,11 +945,14 @@ int main(int argc, char* argv[])
                 app.isPlaying = false;
                 app.playbackFinished = true;
             }
-            // Track playhead position manually
+            // Track playhead position manually, against the length of the buffer
+            // that's actually playing (see playDuration) rather than a length
+            // re-derived from the live selection — the user can move the
+            // selection mid-playback without the marker jumping.
             app.playheadElapsed += GetFrameTime();
-            float selectionDuration = (app.sel.timeEnd - app.sel.timeStart) * app.signal.duration;
-            if (selectionDuration > 0) {
-                app.playheadT = app.playheadElapsed / selectionDuration;
+            if (app.playDuration > 0.0f) {
+                app.playheadT = app.playheadElapsed / app.playDuration;
+                if (app.playheadT > 1.0f) app.playheadT = 1.0f;
             }
         }
 
@@ -1324,8 +1327,13 @@ int main(int argc, char* argv[])
                             app.sel.freqStart = app.sel.freqEnd;
                             app.sel.freqEnd = tmp;
                         }
-                    } else {
-                        // Drag too small - revert to full range
+                    } else if (!hoverInsideSelection) {
+                        // Sub-threshold drag outside any existing selection: treat
+                        // as a click on empty space and reset to full range. A
+                        // stray click *inside* the current box leaves it alone —
+                        // silently clearing it there changes what Space plays.
+                        // (hoverInsideSelection, not clickInsideSelection: the
+                        // latter is press-frame-only and is always false here.)
                         ClearSelection();
                     }
                     app.sel.isTimeSelecting = false;
@@ -1715,7 +1723,7 @@ int main(int argc, char* argv[])
                 app.scopeView.data.sampleRate = app.signal.sampleRate;
                 // Show playhead if playing
                 if (app.isPlaying) {
-                    DrawScopeView(&app.scopeView, app.sel.timeStart + app.playheadT * (app.sel.timeEnd - app.sel.timeStart));
+                    DrawScopeView(&app.scopeView, app.playSelStart + app.playheadT * (app.playSelEnd - app.playSelStart));
                 } else {
                     DrawScopeView(&app.scopeView, -1.0f);
                 }
diff --git a/src/spectrogram_types.h b/src/spectrogram_types.h
index 9a7e580..fbb8a83 100644
--- a/src/spectrogram_types.h
+++ b/src/spectrogram_types.h
@@ -138,9 +138,19 @@ typedef struct {
     bool stftComputed;
 
     // Playback state
-    float playheadT;           // 0-1 normalized position in selection
+    float playheadT;           // 0-1 normalized position within the PLAYING region
     float playheadElapsed;     // Elapsed seconds since play started
 
+    // Snapshot of the region actually handed to the audio device, captured at
+    // PlaySelectedRegion time. The playhead must be measured against this, not
+    // against the live app.sel — the user can move or resize the selection while
+    // audio is still playing, and the marker has to keep tracking the sound
+    // that's really coming out. playDuration comes from the buffer's own sample
+    // count / sampleRate, so it can't drift from app.signal.duration (which is
+    // derived pre-mono-downmix and disagrees for stereo files).
+    float playSelStart, playSelEnd;  // sel.timeStart/End when playback began
+    float playDuration;              // true length of the playing buffer, seconds
+
     // Time + frequency box selection and its drag/move interaction state.
     Selection sel;