I found it has same issue in DDK example, here how to reproduce it:
Modify AVStream\avshws, remove RGB24, just use YUY2, compile and install it.
Test result:
1. Preview avshws with amcap2, start preview > stop preview > start preview , the preview freezed. I found if not rebuild graph, just stop then resume graph, the preview freeze. (YUY2 only, all platform)
2. Preview avshws, then sleep > wake up , the preview freeze. (YUY2 only, vista64 )
3. Preview avshws, then switch user > switch back , the preview freeze. (YUY2 and RGB24, win764)