diff --git a/src/BaseContext.cs b/src/BaseContext.cs
index a8db491..ae364ae 100644
--- a/src/BaseContext.cs
+++ b/src/BaseContext.cs
@@ -157,6 +157,8 @@ private void Dispose(bool disposing)
                 if (disposing)
                 {
                     // TODO: dispose managed state (managed objects)
+                    Timer?.Dispose();
+                    CancellationTokenSource?.Dispose();
                 }
 
                 // TODO: free unmanaged resources (unmanaged objects) and override finalizer
diff --git a/src/Producers/LdapProducer.cs b/src/Producers/LdapProducer.cs
index c5c602a..cb501b3 100644
--- a/src/Producers/LdapProducer.cs
+++ b/src/Producers/LdapProducer.cs
@@ -147,10 +147,9 @@ public override async Task Produce()
 
                             if (searchResult.TryGetDistinguishedName(out var distinguishedName))
                             {
-                                var lower = distinguishedName.ToLower();
-                                if (lower.Contains("cn=domainupdates,cn=system"))
+                                if (distinguishedName.Contains("cn=domainupdates,cn=system", StringComparison.OrdinalIgnoreCase))
                                     continue;
-                                if (lower.Contains("cn=policies,cn=system") && (lower.StartsWith("cn=user") || lower.StartsWith("cn=machine")))
+                                if (distinguishedName.Contains("cn=policies,cn=system", StringComparison.OrdinalIgnoreCase) && (distinguishedName.StartsWith("cn=user", StringComparison.OrdinalIgnoreCase) || distinguishedName.StartsWith("cn=machine", StringComparison.OrdinalIgnoreCase)))
                                     continue;
 
                                 await Channel.Writer.WriteAsync(searchResult, cancellationToken);
@@ -242,4 +241,4 @@ public override async Task ProduceConfigNC()
             }
         }
     }
-}
\ No newline at end of file
+}