Problems with IBasicVideo2.AvgTimePerFrame and DivX 5.1 decoder

[achibus]

I am running into problems with the IBasicVideo2 interface and the AvgTimePerFrame method.

The method returns under following circumstances the value 0.

The video is a DivX 5.1 video in a AVI container
The decoder is DivX 5.1.1

If I use a decoder like ffdshow the method returns the correct value.

But I want to use the standard DivX decoder.

Can someone give me a hint.

Thanks a lot

achibus