problems with brothers CE4000?

I bought a brothers CE4000 and have been having tension problems with it. So i cleaned it out and put it all back together and now I get the E6 error... The fabric keeps getting pulled down into the bobbin area.. Ive taken it all back apart and cleaned it again. I changed the needle, the tread, and the bobbins to make sure I am using the correct produces. Every time I manually turn the needle down into the bottom of the sewing machine I hear a clicking noise that wasn't there before. Now I did take the bobbin case (the brown piece of plastic that the bobbin sits in) out and put it back in..I'm pretty sure I put it in correct. I'm not sure whats going on but I'm about to give up on this machine. Any suggestions? Oh and I called the local sewing shop and they want $75 just to look at it...