Dying during Overthrow Tier 4 turns off the combat music and reverts it back to the open world pale heart themes. Going to a different overthrow area and getting to tier 4 does not turn the combat music back on, nor does going to orbit. You have to fully restart your game then get back to tier 4 to turn the combat music back on. This is mostly frustrating because the exploding seed clusters that spawn in the tier 4 boss arenas will explode randomly and kill you at any distance. It's not a serious game issue but it's a weird one