I subscribe to a service that will raise an Event when a new element is received, I add this element to a `BlockingCollection`.  

I have a second thread running that will loop the `BlockingCollection` to add/update the element in an observable collection.

The problem is how do you do add in the `ObservableCollection`? 
I know I can't just do an `.add` on this type of collection, as it needs to be done on the UI thread. So I tried using different `ObservableCollection` subclass that use the dispatcher to marshal the adding of element, but every single time, I end up with the same error

> 
> "An unhandled exception of type 'System.StackOverflowException'
>  occurred in Unknown Module."
> 
> 
> 

with a troubleshooting tips as:

> 
> make sure you don't have an infinite loop or inifiniterecursion.
> 
> 
> 

Well the thing is, I do have some kind of infinite loop actually, as the `BlockingQueue` is receiving new elements all the time, like 5 to 10 per sec.  

I won't get the exception if I don't bind a control to the `observablecollection` though, or if I use a List instead.

```
Class ElementHolder
{
    private ExternalService _externalService;
    private ObservableCollection<Element> _elementsList = new ObservableCollection<Element>();
    private BlockingCollection<Element> _elementsReceived = new BlockingCollection<Element>();

    public ObservableCollection<Element> ElementsList
    {
        get
        {
            return _elementList;
        }
        set
        {
            _elementList = value;
        }
    }

public ElementHolder()
    {
        Task.Factory.StartNew(ReadElements);
        _externalService = new ExternalService();
        _externalService.ReceivedNewElement += new Action<Element>(o => _elementsReceived.Add(o));
        _externalService.Subscribe();
    }

private void ReadElements()
    {
        foreach (Element element in _elementsReceived.GetConsumingEnumerable())
        {
            Element item = _elementsList.FirstOrDefault(o => o.ID == element.ID);
            if (item == null)
            {
                _elementList.Add(element);
            }
            else
            {
                item.Update(element);
            }
        }
    }

```

EDIT
The bug disappeared by itself, when i was tracking it down. I was trying to make things simpler to really understand where the issue was, and then it started to work. When putting things back together it still works... BUT it comes back time to time, for what seems unrelated reason like adding a style to my listview. I'm starting to think there's an issue in the third party dll.