diff --git a/internal/api/js.go b/internal/api/js.go
index 48ad2ac..3c98e64 100644
--- a/internal/api/js.go
+++ b/internal/api/js.go
@@ -168,12 +168,16 @@ func (c *JSClient) UserID() string {
 // Tests should call stopSyncing() at the end of the test.
 func (c *JSClient) StartSyncing(t *testing.T) (stopSyncing func()) {
 	t.Logf("%s is starting to sync", c.userID)
-	chrome.MustExecute(t, c.ctx, fmt.Sprintf(`window.__client.on("sync", function(state) {
-		if (state !== "PREPARED") {
-			return;
-		}
-		console.log("%s"+"sync||{\"type\":\"sync\",\"content\":{}}");
-	});`, CONSOLE_LOG_CONTROL_STRING))
+	chrome.MustExecute(t, c.ctx, fmt.Sprintf(`
+		var fn;
+		fn = function(state) {
+			if (state !== "SYNCING") {
+				return;
+			}
+			console.log("%s"+"sync||{\"type\":\"sync\",\"content\":{}}");
+			window.__client.off("sync", fn);
+		};
+		window.__client.on("sync", fn);`, CONSOLE_LOG_CONTROL_STRING))
 	ch := make(chan struct{})
 	cancel := c.listenForUpdates(func(roomID string, ev Event) {
 		if roomID != "sync" {
@@ -189,7 +193,6 @@ func (c *JSClient) StartSyncing(t *testing.T) (stopSyncing func()) {
 	}
 	cancel()
 	t.Logf("%s is now syncing", c.userID)
-	time.Sleep(500 * time.Millisecond) // race condition means we don't query keys yet
 	return func() {
 		chrome.AwaitExecute(t, c.ctx, `window.__client.stopClient();`)
 	}
diff --git a/tests/membership_acls_test.go b/tests/membership_acls_test.go
index 9cbaae3..eeaf2fc 100644
--- a/tests/membership_acls_test.go
+++ b/tests/membership_acls_test.go
@@ -52,13 +52,16 @@ func TestAliceBobEncryptionWorks(t *testing.T) {
 
 		// SDK testing below
 		// -----------------
+
+		// login both clients first, so OTKs etc are uploaded.
 		alice := MustLoginClient(t, clientTypeA, api.FromComplementClient(csapiAlice, "complement-crypto-password"), ss)
 		defer alice.Close(t)
+		bob := MustLoginClient(t, clientTypeB, api.FromComplementClient(csapiBob, "complement-crypto-password"), ss)
+		defer bob.Close(t)
 
 		// Alice starts syncing
 		aliceStopSyncing := alice.StartSyncing(t)
 		defer aliceStopSyncing()
-		time.Sleep(time.Second) // TODO: find another way to wait until initial sync is done
 
 		wantMsgBody := "Hello world"
 
@@ -68,11 +71,8 @@ func TestAliceBobEncryptionWorks(t *testing.T) {
 		must.Equal(t, isEncrypted, true, "room is not encrypted when it should be")
 
 		// Bob starts syncing
-		bob := MustLoginClient(t, clientTypeB, api.FromComplementClient(csapiBob, "complement-crypto-password"), ss)
-		defer bob.Close(t)
 		bobStopSyncing := bob.StartSyncing(t)
 		defer bobStopSyncing()
-		time.Sleep(time.Second) // TODO: find another way to wait until initial sync is done
 
 		isEncrypted, err = bob.IsRoomEncrypted(t, roomID)
 		must.NotError(t, "failed to check if room is encrypted", err)