I'm thinking this is a presser foot issue, but not sure if its a "need more" or "need less issue" - or something else Every time I sew a (knit) seam on the serger the perfectly matched up edges get pulled out of alignment - so that the sleeve cuff isnt' quite even at the seam. I've read my serger should pull both pieces of fabric at the same speed so i shouldn't need to pin, but wondering if that would help?
What can I do to fix this?