Hi All, This is my first post in this forum. I am writing a virtual sound driver using MSVAD from winDDK. I am totally new to sound drivers and help is needed. I installed MSVAD simple driver on my box(vadsimpl.sys) and i face these. 1. When i play music using winamp i see that .wav files get created but they dont contain data. 2. I need to implement the WaveIn API using MSVAD, what files should be changed? I see that CSaveData::ReadData is not implemented, i guess it is required for WaveIN calls. Thanks in advance.