AssertionFailure - collection was processed twice by flush() causes Orchard CMS site to crash - nhibernate

Question

I am running Orchard CMS 1.7.2. I created a custom module called BYUtv.Shapes as a place to store reusable shape methods. I have a class called RelatedToShow : IDependency in this module. The method of interest in this class is called RelatedEpisodes. The purpose of this shape method is to retrieve Episodes data, via a query created in the admin ui, for Episodes related to a specific Show. In the manager the Episode content type definition has a Content Picker Field that allows a content manager to pick a Show that the Episode is part of or related to. The query that I created is working correctly and returning the correct data. With that explanation here is my shape method.
[Shape]
public IHtmlString RelatedEpisodes(dynamic Shape, dynamic Display, int? PageSize, string PagerSuffix = "")
{
// Retrieves the QueryPart by name for the query called Related Episodes Year.
// Related Episodes Year retrieves Episodes that are related to a specific show with an optional year filter.
QueryPart episodesQuery = GetQueryPartByName("Related Episodes Year");
dynamic pager = CreatePager(Shape, _projectionManager.GetCount(episodesQuery.Id), PageSize, PagerSuffix);
int startIndex = pager.Pager.GetStartIndex();
int pageSize = pager.Pager.PageSize;
IEnumerable<ContentItem> contentItems = new List<ContentItem>();
if(episodesQuery != null)
{
contentItems = _projectionManager.GetContentItems(episodesQuery.Id, startIndex, pageSize);
}
// Retrieves the QueryPart by name for the query called Related Episodes.
// Related Episodes retrieves Episodes that are related to a specific show.
QueryPart newestEpisodeQuery = GetQueryPartByName("Related Episodes");
ContentItem newestEpisode = null;
if (newestEpisodeQuery != null)
{
newestEpisode = _projectionManager.GetContentItems(newestEpisodeQuery.Id, 0, 1).FirstOrDefault();
}
// Retrieves a list of distinct years that the episodes premiered in.
List<string> years = _projectionManager.GetContentItems(newestEpisodeQuery.Id).Select(y => (string)((dynamic)y).TimeSpanPart.StartDateTime.Year.ToString()).Distinct().ToList();
return Display.RelatedEpisodesView(ContentItems: contentItems, Pager: pager, NewestEpisode: newestEpisode, YearFilter: GetYearFilter(), Years: years);
}
In all my testing this always works locally. It also works in production but seemingly randomly crashes the page it is used on in production. If I comment the code that runs this shape method in production than the rest of the page runs as desired. The only difference that I am aware of between production and local is possibly the HostCompontents.config file and the traffic volume. In production I turn off several properties because I understand it will help performance.
Here are the logs from the production server.
Exception information:
Exception type: AssertionFailure
Exception message: collection was processed twice by flush()
at NHibernate.Engine.Collections.PrepareCollectionForUpdate(IPersistentCollection collection, CollectionEntry entry, EntityMode entityMode, ISessionFactoryImplementor factory) in c:\Users\sebros\Documents\My Projects\nhibernate-core\src\NHibernate\Engine\Collections.cs:line 164
at NHibernate.Event.Default.AbstractFlushingEventListener.FlushCollections(IEventSource session) in c:\Users\sebros\Documents\My Projects\nhibernate-core\src\NHibernate\Event\Default\AbstractFlushingEventListener.cs:line 92
at NHibernate.Event.Default.AbstractFlushingEventListener.FlushEverythingToExecutions(FlushEvent event) in c:\Users\sebros\Documents\My Projects\nhibernate-core\src\NHibernate\Event\Default\AbstractFlushingEventListener.cs:line 61
at NHibernate.Event.Default.DefaultAutoFlushEventListener.OnAutoFlush(AutoFlushEvent event) in c:\Users\sebros\Documents\My Projects\nhibernate-core\src\NHibernate\Event\Default\DefaultAutoFlushEventListener.cs:line 32
at NHibernate.Impl.SessionImpl.AutoFlushIfRequired(ISet`1 querySpaces) in c:\Users\sebros\Documents\My Projects\nhibernate-core\src\NHibernate\Impl\SessionImpl.cs:line 1180
at NHibernate.Impl.SessionImpl.List(String query, QueryParameters queryParameters, IList results) in c:\Users\sebros\Documents\My Projects\nhibernate-core\src\NHibernate\Impl\SessionImpl.cs:line 616
at NHibernate.Impl.SessionImpl.List(String query, QueryParameters parameters) in c:\Users\sebros\Documents\My Projects\nhibernate-core\src\NHibernate\Impl\SessionImpl.cs:line 593
at NHibernate.Impl.QueryImpl.List() in c:\Users\sebros\Documents\My Projects\nhibernate-core\src\NHibernate\Impl\QueryImpl.cs:line 64
at NHibernate.Impl.AbstractQueryImpl.UniqueResult() in c:\Users\sebros\Documents\My Projects\nhibernate-core\src\NHibernate\Impl\AbstractQueryImpl.cs:line 960
at Orchard.ContentManagement.DefaultHqlQuery.Count() in c:\Source\BYUB\byuradio2\orchard\src\Orchard\ContentManagement\DefaultHqlQuery.cs:line 212
at Orchard.Projections.Services.ProjectionManager.<GetCount>b__14(IHqlQuery contentQuery)
at System.Linq.Enumerable.WhereSelectEnumerableIterator`2.MoveNext()
at System.Linq.Enumerable.Sum(IEnumerable`1 source)
at Orchard.Projections.Services.ProjectionManager.GetCount(Int32 queryId)
at BYUtv.Shapes.Drivers.RelatedToShow.RelatedEpisodes(Object Shape, Object Display, Nullable`1 PageSize, String PagerSuffix)
and
Stack trace: at NHibernate.Engine.Collections.PrepareCollectionForUpdate(IPersistentCollection collection, CollectionEntry entry, EntityMode entityMode, ISessionFactoryImplementor factory) in c:\Users\sebros\Documents\My Projects\nhibernate-core\src\NHibernate\Engine\Collections.cs:line 164
at NHibernate.Event.Default.AbstractFlushingEventListener.FlushCollections(IEventSource session) in c:\Users\sebros\Documents\My Projects\nhibernate-core\src\NHibernate\Event\Default\AbstractFlushingEventListener.cs:line 92
at NHibernate.Event.Default.AbstractFlushingEventListener.FlushEverythingToExecutions(FlushEvent event) in c:\Users\sebros\Documents\My Projects\nhibernate-core\src\NHibernate\Event\Default\AbstractFlushingEventListener.cs:line 61
at NHibernate.Event.Default.DefaultAutoFlushEventListener.OnAutoFlush(AutoFlushEvent event) in c:\Users\sebros\Documents\My Projects\nhibernate-core\src\NHibernate\Event\Default\DefaultAutoFlushEventListener.cs:line 32
at NHibernate.Impl.SessionImpl.AutoFlushIfRequired(ISet`1 querySpaces) in c:\Users\sebros\Documents\My Projects\nhibernate-core\src\NHibernate\Impl\SessionImpl.cs:line 1180
at NHibernate.Impl.SessionImpl.List(String query, QueryParameters queryParameters, IList results) in c:\Users\sebros\Documents\My Projects\nhibernate-core\src\NHibernate\Impl\SessionImpl.cs:line 616
at NHibernate.Impl.SessionImpl.List(String query, QueryParameters parameters) in c:\Users\sebros\Documents\My Projects\nhibernate-core\src\NHibernate\Impl\SessionImpl.cs:line 593
at NHibernate.Impl.QueryImpl.List() in c:\Users\sebros\Documents\My Projects\nhibernate-core\src\NHibernate\Impl\QueryImpl.cs:line 64
at NHibernate.Impl.AbstractQueryImpl.UniqueResult() in c:\Users\sebros\Documents\My Projects\nhibernate-core\src\NHibernate\Impl\AbstractQueryImpl.cs:line 960
at Orchard.ContentManagement.DefaultHqlQuery.Count() in c:\Source\BYUB\byuradio2\orchard\src\Orchard\ContentManagement\DefaultHqlQuery.cs:line 212
at Orchard.Projections.Services.ProjectionManager.<GetCount>b__14(IHqlQuery contentQuery)
at System.Linq.Enumerable.WhereSelectEnumerableIterator`2.MoveNext()
at System.Linq.Enumerable.Sum(IEnumerable`1 source)
at Orchard.Projections.Services.ProjectionManager.GetCount(Int32 queryId)
at BYUtv.Shapes.Drivers.RelatedToShow.RelatedEpisodes(Object Shape, Object Display, Nullable`1 PageSize, String PagerSuffix)
The error seems to always relate to collection was processed twice by flush(). I have even tried creating the query directly in the code with similar results.
Another question that was posted is Orchard cms 1.7.2 GenericADOException. Some of the side effects expressed there are similar to what I am having.
Are there any glaring issues that you can see in this code that are causing these errors?
Have you run into this or similar issues?
Any thoughts on how to resolve this problem?