[RFI] USB HUB noise

[Jorge Diez - CX6VM]

Hello

today I needed a RS232 to USB cable, and I found that I have one connected
to a USB hub, but actually disconnected from the radio. I use it to second
radio when doing SO2R, but after contests I take the 2nd radio to home,
just disconnected cable from radio and left USB side connected to USB hub

well, when i disconnected cable from the hub, I noticed that noise in the
radio drop a lot!

So now I am thinking the other RS232 to USB cable and other usb cables I am
using on this hub are making noise

Maybe the hub is a cheap and bad one?

Any recommendation for a noise free USB hub?

thanks!
Jorge
CX6VM/CW5W