minor changes

Jellyfin.Api/Controllers/DynamicHlsController.cs

@@ -1579,6 +1579,8 @@ namespace Jellyfin.Api.Controllers
                     }
                 }
 
+                args += " -start_at_zero";
+
                 // args += " -flags -global_header";
             }
             else

Jellyfin.Api/Controllers/VideoHlsController.cs

@@ -567,6 +567,8 @@ namespace Jellyfin.Api.Controllers
                         args += " " + bitStreamArgs;
                     }
                 }
+
+                args += " -start_at_zero";
             }
             else
             {