I have never had this problem before with this garments, but we are sewing a simple text embroidery design on thin tee like fabric (about as thin as wick away) and holes keep popping up in between the letters and inside the openings of the e's and g's, for instance. The letters range from small, .25" to larger, 1". The small letters are sewing the best. The lettering is fat and sewn in a satin stitch. We have tried less stitches, until it got too sparse, less underlay. Different types of underlay. Different types of backing and combinations there of. Any suggestions?