Managing separate audio volumes in a VMR scenario

[Orf]

I hope not to be OT here, but it's a question about DirecShow.

Let's say I'm using a graph with two A/V sources connected to a 2-pin VMR. I can handle a crossfade between them modifying the alpha value of them.
But the volume of the two clips remains constant!
I expected to find somewhere in the graph a filter with property which would allow me to change independently the audio volume of each clip...
Maybe I have to insert in the graph a filter to handle audio volume... I can't find a filter of this kind... and I'm NOT willing to write this filter by myself!
Any idea?

P.S. I see DirectShow isn't a hot topic here. Can anyone suggest me some resources, maybe another forum more devoted to DirectShow?

Thanks.

[Orf]

Just in case this topic is of some interest: I discovered how to do. You have to build a filter graph for each A/V source and play them together in a "custom allocator/presenter scenario" like the one described in VMRMulti. Thus, manipulating the IBaseAudio interface of each filter graph you can manage the volumes independently.

...am I talking to myself :ehh: ?