Software flow offloading

@fvlaicu if I understand correctly, it might be a known issue with possibly no fix.

@hnyman in the context of your comment, it makes no difference whether the offloading is SW or HW, based, right?

I have just enabled the SW offloading, out of curiosity, though I don't know how much of a difference it will make on a crappy DSL :stuck_out_tongue: