diff --git a/matrix-sdk-android-rx/src/main/java/im/vector/matrix/rx/RxRoom.kt b/matrix-sdk-android-rx/src/main/java/im/vector/matrix/rx/RxRoom.kt
index 02a72777fe..193b5c3fbf 100644
--- a/matrix-sdk-android-rx/src/main/java/im/vector/matrix/rx/RxRoom.kt
+++ b/matrix-sdk-android-rx/src/main/java/im/vector/matrix/rx/RxRoom.kt
@@ -36,7 +36,7 @@ class RxRoom(private val room: Room) {
     fun liveRoomSummary(): Observable<Optional<RoomSummary>> {
         return room.getRoomSummaryLive()
                 .asObservable()
-                .startWith(room.roomSummary().toOptional())
+                .startWithCallable { room.roomSummary().toOptional() }
     }
 
     fun liveRoomMembers(queryParams: RoomMemberQueryParams): Observable<List<RoomMemberSummary>> {
diff --git a/matrix-sdk-android-rx/src/main/java/im/vector/matrix/rx/RxSession.kt b/matrix-sdk-android-rx/src/main/java/im/vector/matrix/rx/RxSession.kt
index c43616f574..2cd2bf2dd3 100644
--- a/matrix-sdk-android-rx/src/main/java/im/vector/matrix/rx/RxSession.kt
+++ b/matrix-sdk-android-rx/src/main/java/im/vector/matrix/rx/RxSession.kt
@@ -110,12 +110,16 @@ class RxSession(private val session: Session) {
     }
 
     fun liveUserCryptoDevices(userId: String): Observable<List<CryptoDeviceInfo>> {
-        return session.getLiveCryptoDeviceInfo(userId).asObservable()
+        return session.getLiveCryptoDeviceInfo(userId).asObservable().startWithCallable {
+            session.getCryptoDeviceInfo(userId)
+        }
     }
 
     fun liveCrossSigningInfo(userId: String): Observable<Optional<MXCrossSigningInfo>> {
         return session.getCrossSigningService().getLiveCrossSigningKeys(userId).asObservable()
-                .startWith(session.getCrossSigningService().getUserCrossSigningKeys(userId).toOptional())
+                .startWithCallable {
+                    session.getCrossSigningService().getUserCrossSigningKeys(userId).toOptional()
+                }
     }
 }