Frankly speaking, these are my first studio monitor, Before purchasing, I had great feelings about the sound. But I dissapointed when I first plug the monitors. a "Hass" sound always keep going, even not plug any instrument, just because of plugging the monitors to electric.
And even I experienced that when I plug the monitors and my lap-top in the same socket, the drum sound (e.g. kick, snare) have snap, crakle and pops. This was really annoying. So I recommend to plug the monitors completely seperated socket. But for notice, "Hass" sound still is continuing. BTW, I have used to it, it doesn't bother me anymore. If this product had magnetical shied, maybe deep noise will be avoided, I don't know.
Here are the official link which has really good recommedations to prevent deep noise: a conclusion, If you're an addict to really clean sound without any deep noise, you should have really good electric. For me, now I started to investigate power conditioner, maybe it can work.
Don't forget, there are almost an addional cost for music lovers.