Android Pitch and Roll Issue

I am working on a tilt app for Android. I am having an issue with Portrait & landscape mode. When the pitch = 90 degrees (phone on end) and even slightly before the roll value goes crazy when there has been no physical change in roll. I have not been able to find a solution to this problem. If anyone can point me in the right direction, it would be appreciated.

Here's a short code dump, so you know it is not an accelerometer error.

final SensorEventListener mEventListener = new SensorEventListener(){
      public void onAccuracyChanged(Sensor sensor, int accuracy) {}  
  public void onSensorChanged(SensorEvent event) {
      setListners(sensorManager, mEventListener);
 
       SensorManager.getRotationMatrix(mRotationMatrix, null, mValuesAccel, mValuesMagnet);
      SensorManager.getOrientation(mRotationMatrix, mValuesOrientation);
 
 
         synchronized (this) {
 
             switch (event.sensor.getType()){
                 case Sensor.TYPE_ACCELEROMETER:
 
                     System.arraycopy(event.values, 0, mValuesAccel, 0, 3);
 
                     long actualTime = System.currentTimeMillis();
 
                     //Sensitivity delay
                     if (actualTime - lastUpdate < 250) {
                         return;
                         }
                     else {
                         sysAzimuth = (int)Math.toDegrees(mValuesOrientation[0]);
                         sysPitch = (int)Math.toDegrees(mValuesOrientation[1]);
                         sysRoll = (int)Math.toDegrees(mValuesOrientation[2]);
 
                         //invert direction with -1
                       pitch = (sysPitch - pitchCal)*-1;
                       roll = (sysRoll - rollCal);
                       azimuth = sysAzimuth;
 
                     lastUpdate = actualTime;
                     }
 

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