diff --git a/Diz.Core.Interfaces/ModelInterfaces.cs b/Diz.Core.Interfaces/ModelInterfaces.cs
index 9558d7d3..4bcd8ec2 100644
--- a/Diz.Core.Interfaces/ModelInterfaces.cs
+++ b/Diz.Core.Interfaces/ModelInterfaces.cs
@@ -188,7 +188,7 @@ public interface IData :
         // TODO: temp hack for serialization, do this better somehow.
         Dictionary<int, IAnnotationLabel> LabelsSerialization { get; }
         
-        public ObservableDictionary<int, string> Comments { get; }
+        public SortedDictionary<int, string> Comments { get; }
     }
 
     public static class DataExtensions
diff --git a/Diz.Core/model/LabelProvider.cs b/Diz.Core/model/LabelProvider.cs
index fc924b6e..31e3ff04 100644
--- a/Diz.Core/model/LabelProvider.cs
+++ b/Diz.Core/model/LabelProvider.cs
@@ -252,7 +252,7 @@ public void AddLabel(int snesAddress, IAnnotationLabel labelToAdd, bool overwrit
     public class LabelsCollection : LabelProviderBase, ILabelService, IEquatable<LabelsCollection>
     {
         // ReSharper disable once MemberCanBePrivate.Global
-        public Dictionary<int, IAnnotationLabel> Labels { get; } = new();
+        public SortedDictionary<int, IAnnotationLabel> Labels { get; } = new();
         
         [XmlIgnore]
         IEnumerable<KeyValuePair<int, IAnnotationLabel>> IReadOnlyLabelProvider.Labels => Labels;
diff --git a/Diz.Core/model/snes/Data.cs b/Diz.Core/model/snes/Data.cs
index ceec9ab7..81ebfa65 100644
--- a/Diz.Core/model/snes/Data.cs
+++ b/Diz.Core/model/snes/Data.cs
@@ -5,7 +5,6 @@
 using System.Xml.Serialization;
 using Diz.Core.Interfaces;
 using Diz.Core.util;
-using IX.Observable;
 
 namespace Diz.Core.model.snes;
 
@@ -15,7 +14,7 @@ public class Data : IData
     public IDataStoreProvider<IArchitectureApi> Apis { get; } = new DataStoreProvider<IArchitectureApi>();
     public IDataStoreProvider<IDataTag> Tags { get; } = new DataStoreProvider<IDataTag>();
 
-    private ObservableDictionary<int, string> comments;
+    private SortedDictionary<int, string> comments;
     private RomBytes romBytes;
         
     // NOTE: snes specific stuff (rom map mode/speed) should eventually be removed from here.
@@ -44,7 +43,7 @@ public RomSpeed RomSpeed
     }
 
     // next 2 dictionaries store in SNES address format (since memory labels can't be represented as a PC address)
-    public ObservableDictionary<int, string> Comments
+    public SortedDictionary<int, string> Comments
     {
         get => comments;
         set => this.SetField(PropertyChanged, ref comments, value);
@@ -68,11 +67,11 @@ public RomBytes RomBytes
     IRomBytes<IRomByte> IRomBytesProvider.RomBytes => romBytes;
 
     [XmlIgnore] 
-    public bool RomBytesLoaded { get; set; } = false;
+    public bool RomBytesLoaded { get; set; }
 
     public Data()
     {
-        comments = new ObservableDictionary<int, string>();
+        comments = new SortedDictionary<int, string>();
         Labels = new LabelsServiceWithTemp(this);
         romBytes = new RomBytes();
     }
diff --git a/Diz.Cpu.65816/src/SampleRomData.cs b/Diz.Cpu.65816/src/SampleRomData.cs
index 0292640a..352d4ba9 100644
--- a/Diz.Cpu.65816/src/SampleRomData.cs
+++ b/Diz.Cpu.65816/src/SampleRomData.cs
@@ -215,7 +215,7 @@ public Data Create()
             new() { Rom = 0x34, TypeFlag = FlagType.Data8Bit, DataBank = 0x80, DirectPage = 0x2100 },
             new() { Rom = 0x6D, TypeFlag = FlagType.Data8Bit, DataBank = 0x80, DirectPage = 0x2100 },
         };
-        data.Comments = new ObservableDictionary<int, string>
+        data.Comments = new SortedDictionary<int, string>
         {
             { 0x808000 + 0x03, "this sets FastROM" },
             { 0x808000 + 0x0F, "direct page = $2100" },