Hello, Can an AVstream driver create an Audio only filter via a filter factory (perhaps in addition to video filters) that are seen as part of mf / mmapi / wasapi? Must I use a portcls driver to do this? I have tried using different KSTOPOLOGY_CONNECTION structures, does an example exist? Thank you in advance. Regards, Richard Lince, Software Engineer. ______________________________________________________________________ This email has been scanned by the Symantec Email Security.cloud service. For more information please visit http://www.symanteccloud.com ______________________________________________________________________