I am wondering if you have the correct needle size...as you say yours is shredding. Is your thread on this project different..as in possibly thicker to cause this problem? The other solutions sound good especially tension issues.. I don't have this machine but was just wondering about the thead shredding problem as that is usually an incorrectly placement/put in needle or that the needle eye is too small for a particular thread. Hope you find out the problem soon as it can be so aggrivating to have these problems.