USB instabilities.

[Philippe Landau]

> USB printer and USB scanner plugged into the same remote hub.
> -------------------------------------------------------------
> Printing will not work as long as the scanner is plugged in to the hub.
> If I remove the scanner and plug it into a usb port on the back of the
> computer, things start to work.  Through out all this the Device manager
> show everything fine.
since years i hear that USB hubs need a separate power supply
to be reliable, and that unpowered USB hubs often lead
to problems like this because the bus power is not sufficient.

kind regards     philippe