diff --git a/src/NzbDrone.Core/Datastore/Migration/162_fix_profile_format_default.cs b/src/NzbDrone.Core/Datastore/Migration/162_fix_profile_format_default.cs
new file mode 100644
index 000000000..8ee7ee293
--- /dev/null
+++ b/src/NzbDrone.Core/Datastore/Migration/162_fix_profile_format_default.cs
@@ -0,0 +1,20 @@
+using FluentMigrator;
+using NzbDrone.Core.Datastore.Migration.Framework;
+
+namespace NzbDrone.Core.Datastore.Migration
+{
+    [Migration(162)]
+    public class fix_profile_format_default : NzbDroneMigrationBase
+    {
+        protected override void MainDbUpgrade()
+        {
+            // badValue was set as default in 147 but it's invalid JSON
+            // so System.Text.Json refuses to parse it (even though Newtonsoft allows it)
+            var badValue = "[{format:0, allowed:true}]";
+            var defaultValue = "[{\"format\":0, \"allowed\":true}]";
+            Alter.Column("FormatItems").OnTable("Profiles").AsString().WithDefaultValue(defaultValue);
+
+            Update.Table("Profiles").Set(new { FormatItems = defaultValue }).Where(new { FormatItems = badValue });
+        }
+    }
+}
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