will a low 60Hz harmonic hum wear out my speakers?

Hi everyone,
I have what is most likely a noob question: I have a nice sounding system consisting of a digital source (newly acquired Oppo BDP 95), a Quad 99 and Quad 909 pre-amp/amp set and Usher tower speakers. The amp generates a continuous, low hum audible in the tweeters. It is only audible with the ear next to the driver, and not an issue in listening. I like to keep everything always on, which is the recommendation I got from Quad and makes sense (it also sounds a lot better to my ears then when turned on fresh and cold). All would be good, but I wonder: in time, will that constant hum wear out or age my tweeters? It is after all the equivalent of constantly playing them but at a very, very low volume. Is this a real concern, or am I being paranoid here?
The issue of what causes the hum and how to get rid of it has been discussed and explored at length without a solution. It is probably the fact that the Quad does not have much in the way of insulation and signal cleaning (built that way) and no amount of power conditioning (I tried) or outlet-plugged signal cleaners etc etc (tried them all) gets rid of it.
Thank you in advance for any advice.