The needle is hitting against the bobbin and the bobbin is also turning slower
(I wish I can add a video so you can see the problem) the bobbin is much slower than it's supposed to and I added oil and it seemed to make it better but not all the way, it still going considerably slower and get's stuck now and then
Sewing Machines - Janome - 2049LX Mechanical Sewing Machine
Answers & Comments
Needle hitting bobbin. It is mistimed. Sounds like it is time to take it in and ask the repair shop to. "Clean, lube, check and time"