Faint buzz in speakers

Gold Note IS-1000MKII integrated amp. Does not fluctuate with volume. Ever so slightly louder (still very faint) in right speaker which is closer to amp. Have not tried removing all interconnects yet. Also, when all breakers in house except stereo circuit are off, same buzz still there.

Thanks to all who’ve chimed in about the buzz in both speakers. Perhaps it does sound more like white noise than a buzz. No, it is not audible from my listening position 8 ft away. In fact, it is so faint you have to place your ear right up against the cone to hear it. I don’t know which is more annoying, the noise itself or the fact that I’ve been unable to track it down. I’ll be sure to  try your suggestions this weekend when I have the time. 

Russ69...I'm the OP. Thank you for the link to this article from Upscale. It's the best explanation I've read on the topic! I would urge anyone with a similar perceived problem to read this. Any frustration over chasing down a faint noise coming from my speakers has been happily replaced with many more worry-free hours of musical bliss. Thanks to everyone who've shown an interest in helping me solve this riddle. Happy Holidays!

@atmasphere @russ69 - You described my concern perfectly. I will simply enjoy listening to my kit & not worry about the faint hiss anymore. Yes, the router is in a less than desirable location, however, I'm stuck with that. Even tried a faraday bag. No change. When router is completely disconnected & all breakers, except for dedicated 20a feeding my gear, the very faint hiss is still there. No change. The link to Upscale's explanation of signal to noise ratio seems spot-on. As I mentioned before, it is not audible from listening position 8ft away. Thanks to everyone & have a peaceful & enjoyable holiday!