>> "There is certainly one very big problem with this topology: a single >> filter cannot be both a source (capturer) and a sink (renderer). " This is not true. The driver can have both a render and capture pin on a single filter. (This is how the USB Audio class driver works.). As to why this is not working, I am not sure. I would need more info on the topology. KsStudio.exe may be your friend here if you have the WDK. DJ From: wdmaudiodev-bounce@xxxxxxxxxxxxx [mailto:wdmaudiodev-bounce@xxxxxxxxxxxxx] On Behalf Of Tim Roberts Sent: Tuesday, January 13, 2009 9:39 AM To: wdmaudiodev@xxxxxxxxxxxxx Subject: [wdmaudiodev] Re: AVStream driver as a both Capture and Renderer Filter swapnil kamble wrote: I am having problems in designing topology for my driver. I have developed Capture/Renderer filter with following topology works perfectly fine for me. ... But when I combine both of them and make topology as, Why are you trying to combine then? I assume here that my pin 0 will become capture pin and pin 2 will become renderer pin. Is there anything mismatching between my assumption and my topology ? There is certainly one very big problem with this topology: a single filter cannot be both a source (capturer) and a sink (renderer). Are you trying to make a transform filter? -- Tim Roberts, timr@xxxxxxxxx<mailto:timr@xxxxxxxxx> Providenza & Boekelheide, Inc.