Do you mean plugging the usb adapter into a usb hub instead of directly in the pc?
I was having problems with that, so eventually used the hub for the other devices (2nd sound card, SDR14...) and left the serial dongles attached to the pc.
However you won't know for sure until you try, as I found that behaviour can be very different depending on the brand of those adapters.
Sometimes the problem can be solved just trying different drivers that may be available for the same chipset.
S