diff --git a/Marr.Data/MapRepository.cs b/Marr.Data/MapRepository.cs
index 25489d15f..c60dc4c09 100644
--- a/Marr.Data/MapRepository.cs
+++ b/Marr.Data/MapRepository.cs
@@ -38,7 +38,7 @@ namespace Marr.Data
         internal Dictionary<Type, string> Tables { get; set; }
         internal Dictionary<Type, ColumnMapCollection> Columns { get; set; }
         internal Dictionary<Type, RelationshipCollection> Relationships { get; set; }
-        internal Dictionary<Type, IConverter> TypeConverters { get; set; }
+        public Dictionary<Type, IConverter> TypeConverters { get; private set; }
 
         // Explicit static constructor to tell C# compiler
         // not to mark type as beforefieldinit
@@ -203,14 +203,7 @@ namespace Marr.Data
         /// <param name="converter">An IConverter object that will handle the data conversion.</param>
         public void RegisterTypeConverter(Type type, IConverter converter)
         {
-            if (TypeConverters.ContainsKey(type))
-            {
-                TypeConverters[type] = converter;
-            }
-            else
-            {
-                TypeConverters.Add(type, converter);
-            }
+            TypeConverters[type] = converter;
         }
 
         /// <summary>
diff --git a/NzbDrone.Core.Test/Datastore/MappingExtentionFixture.cs b/NzbDrone.Core.Test/Datastore/MappingExtentionFixture.cs
index 4324e5aef..6300c6568 100644
--- a/NzbDrone.Core.Test/Datastore/MappingExtentionFixture.cs
+++ b/NzbDrone.Core.Test/Datastore/MappingExtentionFixture.cs
@@ -1,8 +1,10 @@
 using System;
 using System.Collections.Generic;
 using FluentAssertions;
+using Marr.Data;
 using NUnit.Framework;
 using NzbDrone.Core.Datastore;
+using NzbDrone.Core.Datastore.Converters;
 using NzbDrone.Core.Tv;
 
 namespace NzbDrone.Core.Test.Datastore
@@ -35,6 +37,15 @@ namespace NzbDrone.Core.Test.Datastore
             public int WriteOnly { private get; set; }
         }
 
+        [SetUp]
+        public void Setup()
+        {
+            MapRepository.Instance.RegisterTypeConverter(typeof(List<EmbeddedType>), new EmbeddedDocumentConverter());
+            MapRepository.Instance.RegisterTypeConverter(typeof(EmbeddedType), new EmbeddedDocumentConverter());
+            MapRepository.Instance.RegisterTypeConverter(typeof(Int32), new Int32Converter());
+            
+        }
+
 
         [Test]
         public void test_mappable_types()
diff --git a/NzbDrone.Core/Datastore/MappingExtensions.cs b/NzbDrone.Core/Datastore/MappingExtensions.cs
index 7dc1d69c4..468f6bfdf 100644
--- a/NzbDrone.Core/Datastore/MappingExtensions.cs
+++ b/NzbDrone.Core/Datastore/MappingExtensions.cs
@@ -2,6 +2,7 @@
 using System.Collections.Generic;
 using System.Linq;
 using System.Reflection;
+using Marr.Data;
 using Marr.Data.Mapping;
 
 namespace NzbDrone.Core.Datastore
@@ -25,19 +26,18 @@ namespace NzbDrone.Core.Datastore
 
             if (propertyInfo == null) return false;
 
-            if (propertyInfo.PropertyType.GetInterfaces().Any(i => i == typeof(IEmbeddedDocument)))
+
+            if (!propertyInfo.IsReadable() || !propertyInfo.IsWritable())
+            {
+                return false;
+            }
+
+            if (IsSimpleType(propertyInfo.PropertyType) || MapRepository.Instance.TypeConverters.ContainsKey(propertyInfo.PropertyType))
             {
                 return true;
             }
 
-            if (typeof(IEnumerable<IEmbeddedDocument>).IsAssignableFrom(propertyInfo.PropertyType))
-            {
-                return true;
-            }
-
-            var result = propertyInfo.IsReadable() && propertyInfo.IsWritable() && IsSimpleType(propertyInfo.PropertyType);
-
-            return result;
+            return false;
         }
 
         public static bool IsSimpleType(Type type)
diff --git a/NzbDrone.Core/Datastore/TableMapping.cs b/NzbDrone.Core/Datastore/TableMapping.cs
index 5d9cfb287..1343dc38b 100644
--- a/NzbDrone.Core/Datastore/TableMapping.cs
+++ b/NzbDrone.Core/Datastore/TableMapping.cs
@@ -1,7 +1,6 @@
 using System;
 using System.Collections.Generic;
-using System.Linq.Expressions;
-using System.Reflection;
+using System.Linq;
 using Marr.Data;
 using Marr.Data.Mapping;
 using NzbDrone.Core.Configuration;
@@ -16,7 +15,6 @@ using NzbDrone.Core.ReferenceData;
 using NzbDrone.Core.RootFolders;
 using NzbDrone.Core.Tv;
 using BooleanIntConverter = NzbDrone.Core.Datastore.Converters.BooleanIntConverter;
-using System.Linq;
 
 namespace NzbDrone.Core.Datastore
 {
@@ -56,12 +54,28 @@ namespace NzbDrone.Core.Datastore
 
         private static void RegisterMappers()
         {
+            RegisterEmbeddedConverter();
+
             MapRepository.Instance.RegisterTypeConverter(typeof(Int32), new Int32Converter());
             MapRepository.Instance.RegisterTypeConverter(typeof(Boolean), new BooleanIntConverter());
             MapRepository.Instance.RegisterTypeConverter(typeof(Enum), new EnumIntConverter());
-            MapRepository.Instance.RegisterTypeConverter(typeof(QualityModel), new EmbeddedDocumentConverter());
-            MapRepository.Instance.RegisterTypeConverter(typeof(List<MediaCover.MediaCover>), new EmbeddedDocumentConverter());
             MapRepository.Instance.RegisterTypeConverter(typeof(Quality), new QualityIntConverter());
         }
+
+        private static void RegisterEmbeddedConverter()
+        {
+            var embeddedTypes = typeof(IEmbeddedDocument).Assembly.GetTypes()
+                                                          .Where(c => c.GetInterfaces().Any(i => i == typeof(IEmbeddedDocument)));
+
+
+            var embeddedConvertor = new EmbeddedDocumentConverter();
+            var genericListDefinition = typeof(List<>).GetGenericTypeDefinition();
+            foreach (var embeddedType in embeddedTypes)
+            {
+                var embeddedListType = genericListDefinition.MakeGenericType(embeddedType);
+                MapRepository.Instance.RegisterTypeConverter(embeddedType, embeddedConvertor);
+                MapRepository.Instance.RegisterTypeConverter(embeddedListType, embeddedConvertor);
+            }
+        }
     }
 }
\ No newline at end of file
diff --git a/NzbDrone.Core/Qualities/Quality.cs b/NzbDrone.Core/Qualities/Quality.cs
index 0e437a2bc..f327ff892 100644
--- a/NzbDrone.Core/Qualities/Quality.cs
+++ b/NzbDrone.Core/Qualities/Quality.cs
@@ -5,7 +5,7 @@ using NzbDrone.Core.Datastore;
 
 namespace NzbDrone.Core.Qualities
 {
-    public class Quality : IComparable<Quality>, IEmbeddedDocument
+    public class Quality : IComparable<Quality>
     {
         public int Id { get; set; }
         public string Name { get; set; }