diff --git a/Emby.Server.Implementations/Activity/ActivityRepository.cs b/Emby.Server.Implementations/Activity/ActivityRepository.cs
index cac1a9feb4..e45add355f 100644
--- a/Emby.Server.Implementations/Activity/ActivityRepository.cs
+++ b/Emby.Server.Implementations/Activity/ActivityRepository.cs
@@ -15,7 +15,7 @@ namespace Emby.Server.Implementations.Activity
 {
     public class ActivityRepository : BaseSqliteRepository, IActivityRepository
     {
-        private static readonly CultureInfo _usCulture = new CultureInfo("en-US");
+        private static readonly CultureInfo _usCulture = CultureInfo.ReadOnly(new CultureInfo("en-US"));
         private readonly IFileSystem _fileSystem;
 
         public ActivityRepository(ILoggerFactory loggerFactory, IServerApplicationPaths appPaths, IFileSystem fileSystem)