No mods, guess I'll try validating.

Originally posted by Itharus:

The music didn't change into his awesome song... very sad. Is that a bug or was it removed?

Yep. beat him last night, music kicked in as pr. usual

Hardly worth the fight without the deermetal.

Just killed him a bit ago, had music. Dunno if your issue is mods, random bug, or if you need to validate files.