http://homepage.ntlworld.com/dknpower/bubbles.jpg

What is wrong with that. I have tried temperatures from 210 to 270 and the only difference is that at 270 it's getting a bit brown and smelly.

The bubbles are gas, presumably water but I thought I would ask. It is newly opened and has done this from the minute I opened it. It will not extrude more than about 200 mm before it jams and I have to strip the extruder to get it going again. It seems very treacle ish when extruding, sticky and stringy.