diff --git a/frontend/src/AppState.test.ts b/frontend/src/AppState.test.ts
index b094f59..cd67b41 100644
--- a/frontend/src/AppState.test.ts
+++ b/frontend/src/AppState.test.ts
@@ -242,13 +242,13 @@ describe('stateReducer', () => {
         event: {
           mode: SelectionMode.Normal,
           prevMode: SelectionMode.Selecting,
-          selection: { x1: 1001, x2: 1200 },
+          selection: { x1: 1100, x2: 1200 },
         },
         playState: PlayState.Playing,
         position: { frame: 22000, currentTime: 0.4988, percent: 4.98 },
         viewport: { start: 0, end: 88200 },
-        wantSelection: { start: 44144, end: 52920 },
-        wantCurrentTime: 1.000997732426304,
+        wantSelection: { start: 48510, end: 52920 },
+        wantCurrentTime: 1.1,
       },
       {
         name: 'playing, selection is ending, currFrame is within selection',
@@ -312,4 +312,76 @@ describe('stateReducer', () => {
       }
     );
   });
+
+  describe('positionchanged', () => {
+    describe.each([
+      {
+        name: 'playing, 48k',
+        audioSampleRate: 48000,
+        newCurrentTime: 0.02,
+        position: { frame: 0, currentTime: 0, percent: 0 },
+        selection: { start: 0, end: 0 },
+        wantPosition: {
+          frame: 960,
+          currentTime: 0.02,
+          percent: 0.21768707482993196,
+        },
+        wantCurrentTime: undefined,
+        wantPlayState: PlayState.Playing,
+      },
+      {
+        name: 'playing, 44.1k',
+        audioSampleRate: 44100,
+        newCurrentTime: 8.51,
+        position: { frame: 360000, currentTime: 8.16, percent: 81.6 },
+        selection: { start: 0, end: 0 },
+        wantPosition: { frame: 375291, currentTime: 8.51, percent: 85.1 },
+        wantCurrentTime: undefined,
+        wantPlayState: PlayState.Playing,
+      },
+      {
+        name: 'playing, passed selection end',
+        audioSampleRate: 44100,
+        newCurrentTime: 8.51,
+        position: { frame: 360000, currentTime: 8.16, percent: 81.6 },
+        selection: { start: 22050, end: 375290 },
+        wantPosition: { frame: 375291, currentTime: 8.51, percent: 85.1 },
+        wantCurrentTime: 0.5,
+        wantPlayState: PlayState.Paused,
+      },
+    ])(
+      '$name',
+      ({
+        audioSampleRate,
+        newCurrentTime,
+        position,
+        selection,
+        wantPosition,
+        wantCurrentTime,
+        wantPlayState,
+      }) => {
+        it('generates the expected state', () => {
+          const mediaSet = MediaSet.fromPartial({
+            id: '123',
+            audioFrames: 441000,
+            audioSampleRate: audioSampleRate,
+          });
+          const state = stateReducer(
+            {
+              ...initialState,
+              playState: PlayState.Playing,
+              mediaSet,
+              position,
+              selection,
+            },
+            { type: 'positionchanged', currentTime: newCurrentTime }
+          );
+
+          expect(state.position).toEqual(wantPosition);
+          expect(state.playState).toEqual(wantPlayState);
+          expect(state.currentTime).toEqual(wantCurrentTime);
+        });
+      }
+    );
+  });
 });