diff --git a/packages/core/src/audio/audioFxGraph.test.ts b/packages/core/src/audio/audioFxGraph.test.ts
index 4d85eca285..1a8d235196 100644
--- a/packages/core/src/audio/audioFxGraph.test.ts
+++ b/packages/core/src/audio/audioFxGraph.test.ts
@@ -461,3 +461,31 @@ describe("phaser automation targets", () => {
     expect(handle.automation?.out_gain?.[0]?.param.value).toBeCloseTo(0.5, 6);
   });
 });
+
+describe("chain update keeps ids with their effects", () => {
+  const band = (id: string, frequency: number) => ({
+    type: "peaking",
+    id,
+    enabled: true,
+    params: { ...defaultAudioFxParams("peaking"), frequency },
+  });
+
+  /**
+   * Reordering two effects of the same type leaves the shape string identical,
+   * so the chain updates in place rather than rebuilding — correct for the
+   * audio, since the params move with the position. The ids have to move too:
+   * a lane addresses its effect by id, and an id captured at build time names
+   * whichever effect used to occupy that slot. The scheduler would then drive
+   * `fx.n2.frequency` into the band that is now n1 — the exact swap that
+   * HfAudioFxNode.id documents itself as preventing, and the one the voiceover
+   * carve's all-peaking chains make easy to hit.
+   */
+  it("moves an id with its slot when same-type effects are reordered", () => {
+    const chain: HfAudioFxChain = { version: 1, nodes: [band("n1", 200), band("n2", 4000)] };
+    const handle = buildFxChain(ctx() as unknown as BaseAudioContext, chain);
+
+    const swapped: HfAudioFxChain = { version: 1, nodes: [band("n2", 4000), band("n1", 200)] };
+    expect(handle.update(swapped)).toBe(true);
+    expect(handle.nodes.map((n) => n.id)).toEqual(["n2", "n1"]);
+  });
+});
diff --git a/packages/core/src/audio/audioFxGraph.ts b/packages/core/src/audio/audioFxGraph.ts
index abb1f2e5f0..09f3c91a7a 100644
--- a/packages/core/src/audio/audioFxGraph.ts
+++ b/packages/core/src/audio/audioFxGraph.ts
@@ -515,7 +515,17 @@ export function buildFxChain(ctx: BaseAudioContext, chain: HfAudioFxChain): FxCh
       if (shapeOf(next) !== shape) return false;
       const active = next.nodes.filter((node) => node.enabled !== false);
       active.forEach((node, i) => {
-        handles[i]?.handle.update(normalizeAudioFxParams(node.type, node.params));
+        const held = handles[i];
+        if (!held) return;
+        held.handle.update(normalizeAudioFxParams(node.type, node.params));
+        // The id follows the position, because the params just did. Reordering
+        // two effects of the same type leaves the shape identical, so the graph
+        // is updated in place — but a lane addresses its effect BY id, and an id
+        // captured at build time then names whichever effect used to be here.
+        // The scheduler would drive `fx.n2.frequency` into the band that is now
+        // n1: exactly what HfAudioFxNode.id documents itself as preventing.
+        if (node.id === undefined) delete held.id;
+        else held.id = node.id;
       });
       shape = shapeOf(next);
       return true;