mine finally diagnosed was relay rosak (the relay inside the fuse box at the engine bay) . at first they thought is the HU wiring kacau. Exactly same problem you describe above.

The push button will be next to kong coz i have pressed it more than 30 times to get it started just once the last round before it was sent in for a week.

The other time i read about this problem was the switch at the keyless unlock at drivers door kong, that one also will interfere and cause the car to cannot start.

The tell tale sign of all these going crazy is if you DON'T hear the 'zett' sound from the steering motorized lock whenever you shut off the engine and open your driver door... this is what i experienced... so far so good, just didn't 'zett' once 2 days ago. i'm still monitoring the problem if it will keep persisting 

i think the head of the electronics division has spent a lot of time inside my car... it was like a post mortem case before the diagnosed the issue..lol!! good training ground for the newbies.