My car makes the noise as well and it is very annoying. Sitting at idle, warm exhuast, and no radio, I can clearly hear it. You really noitce it when you turn your head
. Just a guess, the ecu must be under the passenger side glove box area. That is where I hear the sound eminating from. I do not hear well to begin with, due to my line of work, but even I can hear it. If your car were to make this noise I feel you would also hear it with out a problem. If you do not hear it no worries for you. Hope the OP is not a troll.