I know where you are coming from. The best thing for the pot would be to completely empty it and clean it. That is the only way that I can get the one that I have to stop. As far as the heads it sounds like the lead may not be hot enough. You really need to mess with the temp. I suggest to pour the lead in the mold over and over until you get a good consistant jig head then add the hooks and swivels.
Hope this helps.