So I have had a dyson v11 oversize stick vacuum for years, loved it so much I got the submarine.  The mop function is a total disappointment, does not remove anything from floor but dust and undried liquid and after 5 minutes of use dirty water sloshs out on the floor from containment unit.  The vacuum however has great suction and seems to pick up even christmas glitter from floor which would be enough of a reason to keep it except the rug attachment wont work on flat rugs or shag rugs in either circumstance the roller hits the rug and stops spinning.  Sounds like its creating a vacuum seal on my persian carpet and on my super shags it sucks in the shag and roller turns off.  I tried adjusting the + and - on the front of the attachment but to no avail. My v11 handles both of these just fine but I cant get the new one to work at all.  Any guidance or do I just return this thing?