My SR makes very similiar tick as this (although not as bad) when it's warm, but runs very smoothly when cold.
https://www.youtube.com/watch?v=L_Yf07HbUlw
Previous owner had changed the lifters and the VTC sprocket but the sound still comes once the engine is warmed up.
However sometimes when I drive on highways or accelerate a lot it sounds smooth again on idle. Do the lifters get more oil on higher revs and thus not being as loud? Or what could it be?