I do have the source.. yes.. but it's in VB5 or VB6 format.. which is different to VB .net. When they converted to .net they axed a few things and added a few things and renamed a few things and made it difficult for everyone 
Turns out I am having problems still. I've got the following problems:
a) While I can open an ogg file and play the whole file, I don't have the ability to change the cooperativelevel (playing global or specific to the app). It seems to be the fact that you used DSSCL_EXCLUSIVE as your cooperative level and for some silly reason my setup doesn't like that. Whether it's .net or DirectSound 9.. I have no idea. So I'm rewriting parts of your vbogg dll to contain this:
pDS->SetCooperativeLevel( hWnd, DSSCL_PRIORITY); //DSSCL_EXCLUSIVE ); //DSSCL_NORMAL ); // DSSCL_PRIORITY );
I've added "priority" there instead of "exclusive". I dunno why, but apparently exclusive doesn't exist with my DS install.
b) I can't change the volume while the file is playing. I haven't even tried to find out why and fix it yet, so yeah 
Anyways, once I've done the full conversion to .net I'll probably post a link to a zip of the project files. I just won't have the "global" or the "pan" options available since I have no reason to spend time on them (I'm not being paid for that!
).
Anyways, back to it..