Well I think you've identified the issue....

Most of my music is still on the SD card in the Music folder....not sure how I browse to that ?

However, just to test, I've copied some tracks into the "Audio Clips" folder on the n900 partition, and run the command as follows below:

All the tracks appear to show as Track 0.....even though the other metadata has been carried across correctly.

How can I correct this ?