Program: 20013
Project: 20013
Buggy source:
@Override protected void onCreate(Bundle _savedInstanceState){
  final XmlWriter writer=new XmlWriter();
  super.onCreate(_savedInstanceState);
  addPreferencesFromResource(R.layout.settings);
  final Preference particlesPref=(Preference)findPreference("String_Node_Str");
  final Preference musicPref=(Preference)findPreference("String_Node_Str");
  final Preference soundsPref=(Preference)findPreference("String_Node_Str");
  SharedPreferences prefs=PreferenceManager.getDefaultSharedPreferences(this);
  particleState=prefs.getBoolean("String_Node_Str",false);
  musicState=prefs.getBoolean("String_Node_Str",true);
  soundState=prefs.getBoolean("String_Node_Str",true);
  writer.saveSettings(particleState,musicState,soundState);
  particlesPref.setOnPreferenceClickListener(new OnPreferenceClickListener(){
    public boolean onPreferenceClick(    Preference preference){
      particleState=((CheckBoxPreference)particlesPref).isChecked();
      musicState=((CheckBoxPreference)musicPref).isChecked();
      soundState=((CheckBoxPreference)soundsPref).isChecked();
      writer.saveSettings(particleState,musicState,soundState);
      return true;
    }
  }
);
  musicPref.setOnPreferenceClickListener(new OnPreferenceClickListener(){
    public boolean onPreferenceClick(    Preference preference){
      particleState=((CheckBoxPreference)particlesPref).isChecked();
      musicState=((CheckBoxPreference)musicPref).isChecked();
      soundState=((CheckBoxPreference)soundsPref).isChecked();
      XmlWriter writer=new XmlWriter();
      writer.saveSettings(particleState,musicState,soundState);
      return true;
    }
  }
);
  soundsPref.setOnPreferenceClickListener(new OnPreferenceClickListener(){
    public boolean onPreferenceClick(    Preference preference){
      particleState=((CheckBoxPreference)particlesPref).isChecked();
      musicState=((CheckBoxPreference)musicPref).isChecked();
      soundState=((CheckBoxPreference)soundsPref).isChecked();
      XmlWriter writer=new XmlWriter();
      writer.saveSettings(particleState,musicState,soundState);
      return true;
    }
  }
);
}

Fixed version (ground truth):
@Override protected void onCreate(Bundle _savedInstanceState){
  final XmlWriter writer=new XmlWriter();
  super.onCreate(_savedInstanceState);
  addPreferencesFromResource(R.layout.settings);
  final Preference particlesPref=(Preference)findPreference("String_Node_Str");
  final Preference musicPref=(Preference)findPreference("String_Node_Str");
  final Preference soundsPref=(Preference)findPreference("String_Node_Str");
  SharedPreferences prefs=PreferenceManager.getDefaultSharedPreferences(this);
  particleState=prefs.getBoolean("String_Node_Str",false);
  musicState=prefs.getBoolean("String_Node_Str",true);
  soundState=prefs.getBoolean("String_Node_Str",true);
  writer.saveSettings(particleState,musicState,soundState);
  particlesPref.setOnPreferenceClickListener(new OnPreferenceClickListener(){
    public boolean onPreferenceClick(    Preference preference){
      particleState=((CheckBoxPreference)particlesPref).isChecked();
      musicState=((CheckBoxPreference)musicPref).isChecked();
      soundState=((CheckBoxPreference)soundsPref).isChecked();
      Options.particles=((CheckBoxPreference)particlesPref).isChecked();
      writer.saveSettings(particleState,musicState,soundState);
      return true;
    }
  }
);
  musicPref.setOnPreferenceClickListener(new OnPreferenceClickListener(){
    public boolean onPreferenceClick(    Preference preference){
      particleState=((CheckBoxPreference)particlesPref).isChecked();
      musicState=((CheckBoxPreference)musicPref).isChecked();
      soundState=((CheckBoxPreference)soundsPref).isChecked();
      Options.music=((CheckBoxPreference)soundsPref).isChecked();
      writer.saveSettings(particleState,musicState,soundState);
      return true;
    }
  }
);
  soundsPref.setOnPreferenceClickListener(new OnPreferenceClickListener(){
    public boolean onPreferenceClick(    Preference preference){
      particleState=((CheckBoxPreference)particlesPref).isChecked();
      musicState=((CheckBoxPreference)musicPref).isChecked();
      soundState=((CheckBoxPreference)soundsPref).isChecked();
      Options.sounds=((CheckBoxPreference)soundsPref).isChecked();
      writer.saveSettings(particleState,musicState,soundState);
      return true;
    }
  }
);
}