AVStream Driver Problem

HI all,
I developed an AVStream based wdm driver for USB device. It exposes two
pins. One is caputure pin and another is still capture pin.I am facing
problem with the pin dispatch function “pinClose”, when i run Windows
Messenger Audio Tuning Wizard. The pinClose for the capture pin is coming
10Secs after the pin state is transition to STOP state. This is only
happening with Windows Messenger Audio Tuning Wizard. The capture pin is
streaming RBG data. I checked with graph edit, there is no problem with
graph edit. Is anybody knows why that delay is occuring between “pin state
STOP” to “PinClose”??
Any pointers or information on this is highly appriciable.
Thanx in advance.

Rafi Maniyar
Tata Elxsi Limited.