Maybe you already do this: Before embroidering, I always spray down the machine with canned air. Include the needle area and especially the bobbin area. For each project, change the needle. Embroidery machines use fast stitches, so the needle must be sharp, and should be an embroidery needle. A titanium needle is a good one for embroidery. A small little nick in the needle can cause the fabric to catch when embroidering. The skipped stitches look like a needle issue, but also looks like a tension issue too. I always practice on a piece of cloth similar to the one embroidering before I go to my final project.