Deadlock with DirectShow during movie playback in WEC7

Combination of Tegra T30, WEC7 and .NET CF 3.5.
We are developing an application that uses DirectShowLib to playback movie files in the order of playlists.
The application uses DirectShow’s “intelligent connection” to build a filter graph and play back the movie.
Looking at the log output by IGraphBuilder.SetLogFile, we are using “NVIDIA Video Renderer”.
However, it suffers from the problem of DirectShow deadlock.

In order to investigate where the deadlock is occurring, I would like to check the status of the DirectShow filter graph, but the following various problems are preventing the investigation

  • Is GraphEdit for WEC7 not provided?

  • If IEnumFilters.Next is called using IEnumFilters obtained with IGraphBuilder.EnumFilters, “NotSupportedException” occurs, but do not you know how to handle it?

  • Since it is stated that using VMR Windowless mode on Microsoft’s site does not cause deadlock, I tried to operate in Windowless mode. While it is possible to play back movies, there seems to be a leakage of COM objects, and as the memory usage increases, the application stops eventually.

I am approaching this problem in various ways, but none have been resolved.
It might be a totally out-of-date question, but I’d appreciate it if there is a little hint.