What's the preferred way to play a sound from a separate file?

[wl2776]

Hi all.
I am writing a media player using GStreamer, in windows.

Some of my files are in DV format, sound and video are stored in separate files: video in .avi, and sound in .wav.
I use playbin2 to play other files. It is unable currently to play a sound from the separate file.

So, what's the preferred way to implement the desired functionality - playbin2 surgery (insertion of another decodebin and one more bin in the playsink), or construction of another gstbin from scratch?

My other problem is that I don't fully understand the purpose of all elements, that were created in the playbin2, when the file is loaded, containing both audio and video data.
It includes GstQueue, GstTee (audiotee), two GstPlaybin2InputSelectors... Why are they all there?
Also, who does provide a clock? I cannot see this on the pictures, generated from dot files.