After 2 replacements and help from 7 or 8 support agents, I consulted this thread and used 'Scott and Helen's' solution- disable UPnP in the EWS window for the printer (did it online through the printer homepage, upper right corner). Worked like a charm and it runs great now. Sure spent a lot of time, gas, and phone minutes getting this solved. HP corporate should bundle a print flyer alert for new units ASAP describing symptoms and solution. This seems to be a widespread problem .
I am a private home user. PS- Various support agents bent over backwards to help me get this solved...