Hi All, I am trying to modify the default wdma_usb.inf to have different a sAPO on the Capture side and the default Microsoft sAPOs on the render side. The defaults for the inf file seems to be controlled via the following lines. [USBAudio.Interfaces] AddInterface=%KSCATEGORY_AUDIO%,"GLOBAL",USBAudio.Interface.Curve, AddInterface=%KSCATEGORY_RENDER%,"GLOBAL",USBAudio.Interface.Curve, AddInterface=%KSCATEGORY_CAPTURE%,"GLOBAL",USBAudio.Interface.Curve, . . . [USBAudio.Interface.Curve] AddReg=USBAudio.Interface.Addreg.Curve, USBAudio.SysFx.Render where the [USBAudio.SysFx.Render] defines the appropiate UIs and APOs. The isse here is that the KSCATEGORY_CAPTURE interface uses the same interface as KSCATEGORY_RENDER. My aim is to retain the Microsoft SysFx on the Render side, but add another interface definition for the capture side, so the INF looks like this. [USBAudio.Interfaces] AddInterface=%KSCATEGORY_AUDIO%,"GLOBAL",USBAudio.Interface.Curve, AddInterface=%KSCATEGORY_RENDER%,"GLOBAL",USBAudio.Interface.Curve, AddInterface=%KSCATEGORY_CAPTURE%,"GLOBAL",USBAudio.CaptureInterface.Curve, . . . [USBAudio.Interface.Curve] AddReg=USBAudio.Interface.Addreg.Curve, USBAudio.SysFx.Render [USBAudio.CaptureInterface.Curve] AddReg=USBAudio.Interface.Addreg.Curve, USBAudio.SysFx.Capture I would have expected the capture device to install the specified capture LFX on the capture side via [USBAudio.SysFx.Capture]. This is failing, i.e. the MS default sAPOs get installed on both render and capture side. I also tried commenting out ;;;;AddInterface=%KSCATEGORY_AUDIO%,"GLOBAL",USBAudio.Interface.Curve, with no success. On the other hand if I use the following, I get my APO and UI installed on the capture device, but my APO and its UI also gets installed on the render device. [USBAudio.Interfaces] AddInterface=%KSCATEGORY_AUDIO%,"GLOBAL",USBAudio.Interface.Curve, ;;;;;AddInterface=%KSCATEGORY_RENDER%,"GLOBAL",USBAudio.Interface.Curve, AddInterface=%KSCATEGORY_CAPTURE%,"GLOBAL",USBAudio.Interface.Curve, . . . [USBAudio.Interface.Curve] AddReg=USBAudio.Interface.Addreg.Curve, USBAudio.SysFx.Capture Where [USBAudio.SysFx.Capture] specifies the capture LFX I am installing with its UI. I tried posting to http://social.msdn.microsoft.com/Forums/en-US/windowspro-audiodevelopment/threads with no response. Would appreciate some help. Thanks Dibyendu db dnandy@xxxxxxxxx