diff --git a/include/utils/TextOutput.h b/include/utils/TextOutput.h
index d8d86ba..de2fbbe 100644
--- a/include/utils/TextOutput.h
+++ b/include/utils/TextOutput.h
@@ -28,8 +28,8 @@
 class TextOutput
 {
 public:
-                        TextOutput() { }
-    virtual             ~TextOutput() { }
+                        TextOutput();
+    virtual             ~TextOutput();
     
     virtual status_t    print(const char* txt, size_t len) = 0;
     virtual void        moveIndent(int delta) = 0;
diff --git a/include/utils/Timers.h b/include/utils/Timers.h
index 9610399..577325f 100644
--- a/include/utils/Timers.h
+++ b/include/utils/Timers.h
@@ -108,15 +108,15 @@
  */
 class DurationTimer {
 public:
-    DurationTimer(void) {}
-    ~DurationTimer(void) {}
+    DurationTimer() {}
+    ~DurationTimer() {}
 
     // Start the timer.
-    void start(void);
+    void start();
     // Stop the timer.
-    void stop(void);
+    void stop();
     // Get the duration in microseconds.
-    long long durationUsecs(void) const;
+    long long durationUsecs() const;
 
     // Subtract two timevals.  Returns the difference (ptv1-ptv2) in
     // microseconds.
diff --git a/include/utils/threads.h b/include/utils/threads.h
index b320915..e0cb664 100644
--- a/include/utils/threads.h
+++ b/include/utils/threads.h
@@ -199,11 +199,11 @@
     // constructed and released when Autolock goes out of scope.
     class Autolock {
     public:
-        inline Autolock(Mutex& mutex) : mpMutex(&mutex) { mutex.lock(); }
-        inline Autolock(Mutex* mutex) : mpMutex(mutex) { mutex->lock(); }
-        inline ~Autolock() { mpMutex->unlock(); }
+        inline Autolock(Mutex& mutex) : mLock(mutex)  { mLock.lock(); }
+        inline Autolock(Mutex* mutex) : mLock(*mutex) { mLock.lock(); }
+        inline ~Autolock() { mLock.unlock(); }
     private:
-        Mutex*  mpMutex;
+        Mutex& mLock;
     };
 
 private:
@@ -291,7 +291,7 @@
             bool        exitPending() const;
     
 private:
-    // Derived class must implemtent threadLoop(). The thread starts its life
+    // Derived class must implement threadLoop(). The thread starts its life
     // here. There are two ways of using the Thread object:
     // 1) loop: if threadLoop() returns true, it will be called again if
     //          requestExit() wasn't called.