Hi, I'm writing full-duplex audio processing code. I've added MS AEC node to the driver stack. In most cases AEC is working fine. But, if user starts playing sound using Wave Out interfaces (for example using Windows Media Player) before our driver has inserted AEC to the driver stack, AEC doesn't work. I can't insert AEC node in topology when user-mode application is using Wave Out. Does anybody have information about it? Is there any known workaround for this problem? Thanks, Alexey