Welcome Sound and Heartbeat

flags related to the availability of the feature

CL_ANN_AMP_TONE_HEARTBEAT
CL_ENT_AMP_TONE_WELCOME
CL_ANN_AMP_MENU_TONE_HEARTBEAT

TONEID_HEARTBEAT
VOLUME_MENU_HEARTBEAT
GREY_OUT_POPUP_HEARTBEAT_CHOICE
VOLUME_HEARTBEAT_RANGE
FOCUS_LISTENER_VOLUME_HEARTBEAT_CHOICE

case 1000034: {
 return "TONE_HEARTBEAT_MAIN";
}

function that enables the sound?

   private boolean isReadinessSoundCoded() {
       return this.env.getSysConst(4596) == 1;
   }

function that triggers the sound

   @Override
   public void play() {
       this.lc.log(-2137614336, "[HeartbeatPlayer.play]");
       this.ringTonePlayer.playTone(this.playMode, 10);
   }

looks like those sound are considered to be ringtones. volume setting might be set to ringtone volume. Or fixed value.

   static /* synthetic */ int access$302(Heartbeat heartbeat, int n) {
       heartbeat.heartbeatVolume = n;
       return heartbeat.heartbeatVolume;
   }

Here's the definition of the volume menu:

   public void createVolumeMenus() {
       this.loweredEntMenus[0] = this.loweredEntAps;
       this.loweredEntMenus[1] = this.loweredEntNav;
       this.menus[3] = new PhoneRingtoneVolumeRange(this);
       this.menus[1] = new TAVolumeRange(this);
       this.menus[2] = new SDSVolumeRange(this);
       this.menus[0] = new NaviVolumeRange(this);
       this.menus[4] = this.loweredEntNav;
       this.menus[5] = this.loweredEntAps;
       this.menus[6] = new TouchpadVolumeRange(this);
       this.menus[7] = new SMSBeepVolumeRange(this);
       this.menus[8] = new HeartbeatVolumeRange(this);
       this.menus[9] = new RingtoneSelectionVolumeRange(this);
       this.menus[10] = new PhoneMicGainVolumeRange(this);
       if (this.env.getSysConst(4162) == 1) {
           this.menus[11] = new WirelessChargingVolumeRange(this);
       }
       this.menus[12] = new InfoAnnouncementVolumeRange(this);
   }

menu[8] is for the sound that we are looking for. Let's check how the HeartbeatVolumeRange class looks like:

public class HeartbeatVolumeRange
extends AbstractVolumeRange {
   private static final int CONNECTION;
   private final int[] volumeConnections = new int[]{48, 82};
   private final int[] greyOutConnections = AudioConnection.GREY_OUT_ALL;
   private final HeartbeatPlayer player;
   private final String name;