Creek 5350SE Startum hum?

Hi all,
I just purchased a sight-unseen Creek 5350SE. It sounds great, but whenever I turn it on from cold, there is a slight hum for the three or so seconds it takes to go from standby to fully on. It is not audible in the speakers and goes away in just a few seconds.

Is this normal, or is this a problem and indicative of something major?

I used to have one, its fine. I still regret selling the one I had. You may have to have the pots cleaned sometime in the future, but its nothing to worry about.