     internal var _videoConfiguration: NextLevelVideoConfiguration?
     internal var _audioConfiguration: NextLevelAudioConfiguration?
     
-    internal var audioQueue: DispatchQueue
-    internal var sessionQueue: DispatchQueue
-    internal var sessionQueueKey: DispatchSpecificKey<NSObject>
-    
-    internal var sessionCurrentClipDuration: CMTime
-    internal var sessionCurrentClipHasAudio: Bool
-    internal var sessionCurrentClipHasVideo: Bool
+    internal var _audioQueue: DispatchQueue
+    internal var _sessionQueue: DispatchQueue
+    internal var _sessionQueueKey: DispatchSpecificKey<NSObject>
+    
+    internal var _currentClipDuration: CMTime
+    internal var _currentClipHasAudio: Bool
+    internal var _currentClipHasVideo: Bool
 
     internal var _clipStarted: Bool
-    internal var timeOffset: CMTime
-    internal var startTimestamp: CMTime
-    internal var lastAudioTimestamp: CMTime
-    internal var lastVideoTimestamp: CMTime
+    internal var _timeOffset: CMTime
+    internal var _startTimestamp: CMTime
+    internal var _lastAudioTimestamp: CMTime
+    internal var _lastVideoTimestamp: CMTime
     
     private let NextLevelSessionAudioQueueIdentifier = "engineering.NextLevel.session.audioQueue"
     private let NextLevelSessionQueueIdentifier = "engineering.NextLevel.sessionQueue"

                
                if let outputBuffer = bufferToProcess {
                    if pixelBufferAdapter.append(outputBuffer, withPresentationTime: offsetBufferTimestamp) {
                        self.sessionCurrentClipDuration = (offsetBufferTimestamp + frameDuration) - self.startTimestamp
                        self.lastVideoTimestamp = timestamp
                        self.sessionCurrentClipHasVideo = true
                        completionHandler(true)
                        return
                    }

                    
                    if writer.startWriting() {
                        self._clipStarted = true
                        self._timeOffset = kCMTimeZero
                        self._startTimestamp = kCMTimeInvalid
                    } else {
                        print("NextLevel, writer encountered an error \(writer.error)")
                        self._writer = nil
