I just noticed how you have threaded the 3-hole thread guide. Did you get that threading from a manual or threading diagram for the machine? If so, then you may want to ignore the rest of this post.
My Voyager 17 is a stretched industrial Singer and has a similar 3-hole thread guide, although mine is slanted. My manual has me threading it differently in that the thread goes through each hole in the same direction (not back and forth). On mine the thread goes left-to-right through each hole.
I'm thinking that the way that 3-hole guide is threaded could be causing your breaks, as the thread will not be evenly tensioned in that area (being threaded left-to-right then right-to-left then left-to-right). I would try threading each hole left-to-right and see how that works. If it's a problem, I would try threading them all right-to-left.