I have a similar problem with my HICAS but now stays on all the time, from what I have read mine is probably the HICAS ECU not working but haven't had the chance to change it over to see if that fixes it, will let you know if I do fix it.
I used to have a similar noise from the engine (was after some spirited driving), oil was a liitle low and sounded like lifter noise changed the oil and noise has basically dissapeared apart from when first started for about 10 seconds. hope this info helps a bit.