What I found works best for ME with metallic thread is slowing the machine
speed down as much as you can, and using a SHARP large eye needle.
The large eye needles have a deeper "groove" for the metallic thread "glide"
through. At least this is what I have recently learned from watching a Quilting
Arts program on PBS and it was Libby Lehman who discussed the different
needles and machine feet etc.
I have also heard that putting the metallic thread in the freezer for about 15
minutes helps, but I have not tried this yet.