I just bought an ultimaker3 and an extra set of heads, both AA and BB. I'm putting PVA through the second head which is a BB and it has jammed and clogged the silver part of the head with PVA. I tried the second head and the same thing happened. I took one of the heads apart and cleaned out the silver tube but I think it is the copper head that is clogging. As soon as I tried it again the head was already clogged. I'm using the default settings and made sure Head 2 was PVA. How can the head clog so quickly? Is this a common problem?