I'm not sure of your noise, but I've had a slight click or knock when turning the steering wheel on occasions, it doesn't seem to be entirely repeatable and I've not really got to grips with exactly what the conditions are for it to happen. It's never been picked up on the MOT where they jack it up wheel-free and turn from lock to lock, so I'm not really sure where it comes from. I always suspected the lower universal joint but it doesn't really seem to be that, or not that I can identify anyway (could be though).
I keep waiting for it to get worse or consistent, but it's been the same for years.