Hi Eva,
Sorry for the long response, I was scrapping with a sewing machine and got a little carried away.
Yes, if A2 is flopping around, then it will cause issues. This is a pretty common problem. The easiest way to fix it, is to remove the needleplate, as if you were going to clean the feed dogs, and reposition the finger to the "upright" position, then carefully place the needle plate back down so that it straddles that finger.
I bet that fixes the problem. If it doesn't, let us know, and I'll post more about the timing issue. By the way, it's pretty rare for a FW to go out of time as far as I can tell, so that's why I said that working through all of the other suggested issues first are the way to go...
Easy as pie! I know you can do it.