BarOpened Event occasionally fires randomly

Morning - 

I have a cBot that relies on the BarOpened event firing once (and only once!) as each bar is closed and a new one opened.  Although this is true about 95% of the time, it can not be relied on as it occasionally fires unpredictably midway through the life of that candle.  I setup a test to see how bad the problem was.  20 pairs on 1hr timeframe logging when the BarOpened event fires.  I ran it for approximately 20 hrs continuously and of the 434 log records, 16 were erroneous (i.e. event fired for a second time between 10 seconds and 58 minutes after the original (correct) bar open event was logged).  This doesn't seem to be the same as the BarOpened event firing on every tick problem that was reported last year, but it is annoying and means I am forced to store and check a 'bar last opened' variable to double check that the BarOpened event is legitimate. Please let me know if I'm misunderstanding anything here.

Thanks

Erroneous results (logs for correct BarOpened events removed):

Test code:

using System;
using System.Linq;
using cAlgo.API;

namespace cAlgo.Robots
{
    [Robot(TimeZone = TimeZones.UTC, AccessRights = AccessRights.FullAccess)]
    public class MisfiringOnBarOpen : Robot
    {

        protected override void OnStart()
        {
            Bars bars1 = MarketData.GetBars(TimeFrame.Hour, "AUDUSD");
            Bars bars2 = MarketData.GetBars(TimeFrame.Hour, "USDJPY");
            Bars bars3 = MarketData.GetBars(TimeFrame.Hour, "USDCAD");
            Bars bars4 = MarketData.GetBars(TimeFrame.Hour, "NZDUSD");
            Bars bars5 = MarketData.GetBars(TimeFrame.Hour, "EURUSD");
            Bars bars6 = MarketData.GetBars(TimeFrame.Hour, "GBPUSD");
            Bars bars7 = MarketData.GetBars(TimeFrame.Hour, "EURGBP");
            Bars bars8 = MarketData.GetBars(TimeFrame.Hour, "AUDJPY");
            Bars bars9 = MarketData.GetBars(TimeFrame.Hour, "GBPJPY");
            Bars bars10 = MarketData.GetBars(TimeFrame.Hour, "EURAUD");
            Bars bars11 = MarketData.GetBars(TimeFrame.Hour, "XAUUSD");
            Bars bars12 = MarketData.GetBars(TimeFrame.Hour, "UK100");
            Bars bars13 = MarketData.GetBars(TimeFrame.Hour, "US2000");
            Bars bars14 = MarketData.GetBars(TimeFrame.Hour, "USDCHF");
            Bars bars15 = MarketData.GetBars(TimeFrame.Hour, "EURJPY");
            Bars bars16 = MarketData.GetBars(TimeFrame.Hour, "EURCHF");
            Bars bars17 = MarketData.GetBars(TimeFrame.Hour, "CADJPY");
            Bars bars18 = MarketData.GetBars(TimeFrame.Hour, "US500");
            Bars bars19 = MarketData.GetBars(TimeFrame.Hour, "US30");
            Bars bars20 = MarketData.GetBars(TimeFrame.Hour, "SpotCrude");

            bars1.BarOpened += Bars_BarOpened;
            bars2.BarOpened += Bars_BarOpened;
            bars3.BarOpened += Bars_BarOpened;
            bars4.BarOpened += Bars_BarOpened;
            bars5.BarOpened += Bars_BarOpened;
            bars6.BarOpened += Bars_BarOpened;
            bars7.BarOpened += Bars_BarOpened;
            bars8.BarOpened += Bars_BarOpened;
            bars9.BarOpened += Bars_BarOpened;
            bars10.BarOpened += Bars_BarOpened;
            bars11.BarOpened += Bars_BarOpened;
            bars12.BarOpened += Bars_BarOpened;
            bars13.BarOpened += Bars_BarOpened;
            bars14.BarOpened += Bars_BarOpened;
            bars15.BarOpened += Bars_BarOpened;
            bars16.BarOpened += Bars_BarOpened;
            bars17.BarOpened += Bars_BarOpened;
            bars18.BarOpened += Bars_BarOpened;
            bars19.BarOpened += Bars_BarOpened;
            bars20.BarOpened += Bars_BarOpened;
        }

        private void Bars_BarOpened(BarOpenedEventArgs obj)
        {
            Print("1Hr BarOpened Event Fired for: {0} - candle index: {1} - candle opentime: {2}", obj.Bars.SymbolName, obj.Bars.Count, obj.Bars.LastBar.OpenTime.ToLocalTime());
        }

    }
}