diff --git a/roomserver/internal/input/input.go b/roomserver/internal/input/input.go
index 1cb980dc3..c47793f0a 100644
--- a/roomserver/internal/input/input.go
+++ b/roomserver/internal/input/input.go
@@ -172,10 +172,12 @@ func (r *Inputer) Start() error {
 		func(m *nats.Msg) {
 			roomID := m.Header.Get(jetstream.RoomID)
 			r.startWorkerForRoom(roomID)
+			_ = m.Ack()
 		},
 		nats.HeadersOnly(),
 		nats.DeliverAll(),
-		nats.AckNone(),
+		nats.AckExplicit(),
+		nats.ReplayInstant(),
 		nats.BindStream(r.InputRoomEventTopic),
 	)
 	return err