I've spent a long time on this one now and still no resolution. I moved the vanilla (i.e. RTW) music idx and dat file into the bi data\sounds along with the vanilla bi DSM - and those worked. I then replaced it with my DSM, making sure the paths were the same, and then replaced the dat and idx. Still nothing.
The only possible problem must be the way xidx is generating the files. Can anyone who has successfully got packed music working for a BI mod please post the command line of their bat file here. Thx. And someone might direct me to the xidx download (I can never seem to find the latest update of tools on any forums); I have version 0.97
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