Yes but that noise is constant all the time, however, I am thinking that maybe as the a/c compressor cut in and out there is a difference in load on the bearing. But as I said, it is hard to understand the noise from what is written in your post.
Changing t/x oil is good but it will have no impact on the noise.
If is is more noticeable at idle then there is something vibrating and it could be two metal things banging against each other. Sitting here it is hard to say what the noise is. Get it checked.