@GCRaistlin, from what you've said so far, I can't really say what is causing your issue.
- First try uninstalling FFDShow entirely. Does the problem occur?
- If not, install the latest ffdshow build if you needed it, and disable all the checkboxes in the FFDSHow subtitle section for good measure.
- Update MPC-HC to the latest nightly build. Reset to defaults. "'Miscellaneous" -> "Setting Management" -> "Reset". Ensure that "Playback" -> "Use built-in subtitle renderer" is disabled. Do not add any 'External Filters'.
- Uninstall XySubFilter. Restore Defaults with the reg file found here.
- Test to ensure you have no problems without XySubFilter installed.
- Install XySubFilter r697 with the bat file. (DLLRegisterServer in XySubFilter.dll succeeded)
- If the problem still occurs, you'll need to provide some more details about the filters being used and how this can be reproduced.