Not at all sure but, try changing the name of your folder inside your intro folder to something else.
The reason I say this is it might be looking for the track in the default Music.pbo.
Now, I was under the impression that it checked in the intro folder first before looking in the default locations, but I might be wrong.
Try changing the folder name....say 'musik'...and alter the description.ext to suit.
I doubt it would work, but, it's worth a try.
Another thing to try, which might not be terribly important, but you never know, is, put quotes around the path.
BIS used quotes in their cfgMusic section in the game config.
Like so:
sound[] = {
"\music\TheGreyHavens.ogg
", db + 40, 1.0};
The volume BIS used was 1.0, the same for the pitch value, for example:
sound[]={"\Music\Seventh_overdose.ogg",
1.0,1.0};
You could possibly try that too. ;D
I don't know if this will be needed but if everything else fails you could alter the path to suit your mission PBO exactly:
sound[] = {
"\Nameofmyintrofolder\music\TheGreyHavens.ogg", db + 40, 1.0};[/b]
Hope some of that will help.
EDIT: Another thing to check is that your music file is 16 bit Stereo 44100 hz 128kbps.
Planck