I've made a disassembly of the music data in SoE (see following download link). I think I am currently close to or on par with what is on the RHDN ROM map. If anyone has ever worked with the game music or BRR data, any new info will be appreciated. I got the BRR samples identified but the rest of the data fetching is a mystery though I suspect long blocks fetching (more than $30 bytes) could be song data. Thanks in advance!
Edit: updated to newer version!
soe-spc-data-v3.zip