Always use Interactive Music Hierarchy instead of Actor-Mixer Hierarchy. Might be harder, but once you learn it, it becomes infinitely better than shit that's used for SFX.
Don't uncheck "Continue to play on Switch change", so you don't have to do that Stealth Looping thing on switch change.
You can always use other options in "Exit source at" other than "Immediate", just make sure to specify song's tempo.