         tester = AKTester(node, samples: samples)
         output = tester
         start()
-        self.engine.pause()
+        engine.pause()
         tester?.play()
-        let renderer = AKOfflineRenderer(engine: self.engine)
+        let renderer = AKOfflineRenderer(engine: engine)
         renderer?.render(Int32(samples))
     }
 

        }
        // Start the engine.
        do {
            self.engine.prepare()

            #if os(iOS)



            #endif

            try engine.start()
            shouldBeRunning = true

        } catch {
