It works fine after I reset the modem, but every 30 mins - 6 hours it gets bad again. I have had 5 business class technicians out here and they have all done different things, but none have worked.
You got a window for SNR( signal to noise ratio)? http://www.dslreports.com/faq/16085 everything seems fine otherwise. The dBmV is in acceptable tolerances. In fact at this point I'd tell them to change the modem you are using.
Your power levels for downstream seem fine as well. I had problems with comcast as well but mine was well above +15 dBmV but yours isn't the case at all... strange...