diff --git a/appservice/consumers/roomserver.go b/appservice/consumers/roomserver.go
index 44ac9fc3e..395fa994c 100644
--- a/appservice/consumers/roomserver.go
+++ b/appservice/consumers/roomserver.go
@@ -81,6 +81,11 @@ func (s *OutputRoomEventConsumer) Start() error {
 func (s *OutputRoomEventConsumer) onMessage(msg *sarama.ConsumerMessage) error {
 	// Parse out the event JSON
 	var output api.OutputEvent
+	if err := json.Unmarshal(msg.Value, &output); err != nil {
+		// If the message was invalid, log it and move on to the next message in the stream
+		log.WithError(err).Errorf("roomserver output log: message parse failure")
+		return nil
+	}
 
 	if output.Type != api.OutputTypeNewRoomEvent {
 		log.WithField("type", output.Type).Debug(
diff --git a/federationsender/consumers/roomserver.go b/federationsender/consumers/roomserver.go
index 0180e38e8..d47254efd 100644
--- a/federationsender/consumers/roomserver.go
+++ b/federationsender/consumers/roomserver.go
@@ -79,6 +79,7 @@ func (s *OutputRoomEventConsumer) onMessage(msg *sarama.ConsumerMessage) error {
 		log.WithError(err).Errorf("roomserver output log: message parse failure")
 		return nil
 	}
+
 	if output.Type != api.OutputTypeNewRoomEvent {
 		log.WithField("type", output.Type).Debug(
 			"roomserver output log: ignoring unknown output type",
@@ -86,6 +87,31 @@ func (s *OutputRoomEventConsumer) onMessage(msg *sarama.ConsumerMessage) error {
 		return nil
 	}
 
+	// Get the room version of the room
+	vQueryReq := api.QueryRoomVersionForRoomIDRequest{RoomID: string(msg.Key)}
+	vQueryRes := api.QueryRoomVersionForRoomIDResponse{}
+	if err := s.query.QueryRoomVersionForRoomID(context.Background(), &vQueryReq, &vQueryRes); err != nil {
+		log.WithFields(log.Fields{
+			"room_id": string(msg.Key),
+		}).WithError(err).Errorf("can't query room version")
+		return err
+	}
+
+	// Prepare the room event so that it has the correct field types
+	// for the room version
+	if err := output.NewRoomEvent.Event.PrepareAs(vQueryRes.RoomVersion); err != nil {
+		log.WithFields(log.Fields{
+			"room_version": vQueryRes.RoomVersion,
+		}).WithError(err).Errorf("can't prepare event to version")
+		return err
+	}
+
+	if err := json.Unmarshal(msg.Value, &output); err != nil {
+		// If the message was invalid, log it and move on to the next message in the stream
+		log.WithError(err).Errorf("roomserver output log: message parse failure")
+		return nil
+	}
+
 	ev := output.NewRoomEvent.Event
 	log.WithFields(log.Fields{
 		"event_id":       ev.EventID(),
diff --git a/publicroomsapi/consumers/roomserver.go b/publicroomsapi/consumers/roomserver.go
index 22584a1d5..c56d8215b 100644
--- a/publicroomsapi/consumers/roomserver.go
+++ b/publicroomsapi/consumers/roomserver.go
@@ -63,6 +63,11 @@ func (s *OutputRoomEventConsumer) Start() error {
 // onMessage is called when the sync server receives a new event from the room server output log.
 func (s *OutputRoomEventConsumer) onMessage(msg *sarama.ConsumerMessage) error {
 	var output api.OutputEvent
+	if err := json.Unmarshal(msg.Value, &output); err != nil {
+		// If the message was invalid, log it and move on to the next message in the stream
+		log.WithError(err).Errorf("roomserver output log: message parse failure")
+		return nil
+	}
 
 	// Filter out any messages that aren't new room events
 	if output.Type != api.OutputTypeNewRoomEvent {