Android推送通知声音仅在应用处于前景时播放,但在应用处于后台时不播放声音

public void playNotificationSound() {
        try {

            Uri notification = @L_821_3@manager.getDefaultUri(@L_821_3@manager.TYPE_NOTIFICATION);
            ringtone r = @L_821_3@manager.getringtone(mCo@R_801_10443@t,notification);
            r.play();

        } catch (Exception E) {
            e.printStackTrace();
        }
    }

我正在调用这个OnmessageReceived方法,但声音仅在应用程序处于前台时播放,而不是在应用程序处于后台时播放

@Override
    public void onmessageReceived(Remotemessage remotemessagE) {
        Log.e@R_675_10374@,"From: " + remotemessage.getFrom());

        if (remotemessage == null)
            return;

        // check if message contains a notification payload.
        if (remotemessage.getNotification() != null) {
            Log.e@R_675_10374@,"Notification Body: " + remotemessage.getNotification().getBody());
            handleNotification(remotemessage.getNotification().getBody());
        }

        // check if message contains a data payload.
        if (remotemessage.getData().size() > 0) {
            Log.e@R_675_10374@,"Data Payload: " + remotemessage.getData().toString());

            try {
                JSONObject json = new JSONObject(remotemessage.getData().toString());
                handleDatamessage(json);
            } catch (Exception E) {
                Log.e@R_675_10374@,"Exception: " + e.getmessage());
            }
        }
    }





 private void handleNotification(String messagE) {
        if (!NotificationUtils.isAppIsInBACkground(getApplicationCo@R_801_10443@t())) {
            // app is in foreground,broadcast the push message
            Intent pushNotification = new Intent(con@L_262_12@.PUSH_NOTIFICATION);
            pushNotification.putExtra("message",messagE);
            LocalBroadcastManager.geTinstance(this).sendBroadcast(pushNotification);

            // play notification sound
            NotificationUtils notificationUtils = new NotificationUtils(getApplicationCo@R_801_10443@t());
            notificationUtils.playNotificationSound();
        }else if (NotificationUtils.isAppIsInBACkground(getApplicationCo@R_801_10443@t())){
            // If the app is in BACkground,firebase itself handles the notification
            NotificationUtils notificationUtils = new NotificationUtils(getApplicationCo@R_801_10443@t());
            notificationUtils.playNotificationSound();
        }
    }