On 2020-04-07, Brian Gaff (Sofa 2) wrote:

What I do not like about usbs built in is that they chuck out crap onto the
mains as the circuits tend to be bought in crap from China. At least if you
get a plug in one, you can unplug it and see if its the guilty party.

Just curious --- what kind of other mains-fed equipment is the noise
interfering with?

I don't that charging circuits can put noise on the lines, but I've
never noticed any effects from it & we have a lot of various DC power
supplies plugged in at the same time in our house.