Error when opening some videos at the same time as the subtitle file

GLib-GIO | Debug | _g_io_module_get_default: Found default implementation gvfs (GDaemonVfs) for ‘gio-vfs’
GLib | Debug | unsetenv() is not thread-safe and should not be used after threads are created
GLib-GIO | Debug | _g_io_module_get_default: Found default implementation dconf (DConfSettingsBackend) for ‘gsettings-backend’
21:35:57.4 INFO [Spellcheck] Found Enchant version: 2
21:35:57.4 INFO [Spellcheck] Found 3 providers: hspell,aspell,hunspell
21:35:57.5 INFO [Spellcheck] Found 7 languages: en,en_AU,en_CA,en_ZA,en_GB,en_US,pt_PT
21:36:04.4 INFO [FileInputOutput] Detected encodings: windows-1252
21:36:04.4 INFO [SubtitleInput] Trying encoding "Windows-1252"
21:36:04.4 INFO [SubtitleInput] Trying to autodetect the subtitle format.
21:36:04.5 INFO [SubtitleFactory] Opened "(...)file.srt" with encoding "I18N.West.CP1252", format "SubRip", timing mode "Times" and frame rate "25" (input frame rate was "25")
21:36:04.6 INFO [GstBackend] Disabling libva
Stream with high frequencies VQ coding
Exception in Gtk# callback delegate
  Note: Applications can use GLib.ExceptionManager.UnhandledException to handle the exception.
System.NullReferenceException: Object reference not set to an instance of an object
  at GLib.Timeout+TimeoutProxy.Handler () [0x0000e] in <4585e411a46b451eac14ce4f86025668>:0 
  at GLib.ExceptionManager.RaiseUnhandledException (System.Exception e, System.Boolean is_terminal) [0x00000] in <4585e411a46b451eac14ce4f86025668>:0 
  at GLib.Timeout+TimeoutProxy.Handler () [0x00000] in <4585e411a46b451eac14ce4f86025668>:0 
  at GLib.Application.g_application_run (System.IntPtr , System.Int32 , System.IntPtr ) [0x00000] in <46b602a63bb84fcea4f86063f00beda0>:0 
  at GLib.Application.Run (System.Int32 argc, System.String argv) [0x00000] in <46b602a63bb84fcea4f86063f00beda0>:0 
  at GnomeSubtitles.Execution.ExecutionContext.Execute (System.Action methodToExecute) [0x00000] in <5725724a15b54d20a54985e0a0ececa8>:0 
  at GnomeSubtitles.Core.Base.Execute (GnomeSubtitles.Execution.ExecutionContext context) [0x00000] in <5725724a15b54d20a54985e0a0ececa8>:0 
  at GnomeSubtitles.Execution.Executable.Main (System.String[] args) [0x00000] in <5725724a15b54d20a54985e0a0ececa8>:100: