diff --git a/extensions/qa-matrix/src/substrate/sync.test.ts b/extensions/qa-matrix/src/substrate/sync.test.ts
index abea4b9c058..dbaacf3f2da 100644
--- a/extensions/qa-matrix/src/substrate/sync.test.ts
+++ b/extensions/qa-matrix/src/substrate/sync.test.ts
@@ -1,4 +1,4 @@
-import { describe, expect, it } from "vitest";
+import { describe, expect, it, vi } from "vitest";
 import type { MatrixQaObservedEvent } from "./events.js";
 import {
   createMatrixQaRoomObserver,
@@ -50,16 +50,22 @@ describe("matrix sync helpers", () => {
 
     const observedEvents: MatrixQaObservedEvent[] = [];
 
-    const result = await waitForOptionalMatrixQaRoomEvent({
-      accessToken: "token",
-      baseUrl: "http://127.0.0.1:28008/",
-      fetchImpl,
-      observedEvents,
-      predicate: (event) => event.sender === "@sut:matrix-qa.test",
-      roomId: "!room:matrix-qa.test",
-      since: "start-batch",
-      timeoutMs: 1_000,
-    });
+    const nowSpy = vi.spyOn(Date, "now").mockReturnValueOnce(0).mockReturnValue(1);
+    let result: Awaited<ReturnType<typeof waitForOptionalMatrixQaRoomEvent>>;
+    try {
+      result = await waitForOptionalMatrixQaRoomEvent({
+        accessToken: "token",
+        baseUrl: "http://127.0.0.1:28008/",
+        fetchImpl,
+        observedEvents,
+        predicate: (event) => event.sender === "@sut:matrix-qa.test",
+        roomId: "!room:matrix-qa.test",
+        since: "start-batch",
+        timeoutMs: 1,
+      });
+    } finally {
+      nowSpy.mockRestore();
+    }
 
     expect(result).toEqual({
       matched: false,
diff --git a/extensions/qa-matrix/src/substrate/sync.ts b/extensions/qa-matrix/src/substrate/sync.ts
index 9d9983eaeae..aafcf4d3536 100644
--- a/extensions/qa-matrix/src/substrate/sync.ts
+++ b/extensions/qa-matrix/src/substrate/sync.ts
@@ -144,6 +144,7 @@ export function createMatrixQaRoomObserver(
       const startSince = await this.prime();
       const startedAt = Date.now();
       let cursorIndex = roomObserver.cursorIndex;
+      let didPoll = false;
       while (true) {
         const matched = findMatrixQaObservedEventMatch({
           cursorIndex,
@@ -161,7 +162,7 @@ export function createMatrixQaRoomObserver(
         }
 
         const elapsedMs = Date.now() - startedAt;
-        if (elapsedMs >= waitParams.timeoutMs) {
+        if (elapsedMs >= waitParams.timeoutMs && (didPoll || waitParams.timeoutMs <= 0)) {
           roomObserver.cursorIndex = Math.max(roomObserver.cursorIndex, cursorIndex);
           return {
             matched: false,
@@ -177,6 +178,7 @@ export function createMatrixQaRoomObserver(
           roomObserver,
           timeoutMs: remainingMs,
         });
+        didPoll = true;
       }
     },
     async waitForRoomEvent(waitParams) {