Avicii:
-Was he suffering from depression as far as he knew?
Yes. But he had a good coexistence with his family and friends.
Subliminal messages in the song "Wake Me Up", yes.
-Wake Me Up narrated Avicii's life in those moments, his depression reflected in the song due to the constant threats of this group of power so that Avicii doesn't declare. Unfortunately, his only way out was death.