I am knot sure what it could be....

Thanks a lot everyone for the funny and different points. I will try to take all of these into consideration next time I go out!

I was having the exact same issue, losing too many jigs....I recently switched to 12# Yozuri and started using a double San diego jam knot....been out a couple time since switching and No lost jigs!

If you're using a short enough leader to use it, use a swivel.  SPRO Power Swivels in the smallest size work nicely.  I had a lot of knot breaking issues too going double-uni braid to fluoro but haven't had any since.

I'll give you the benefit of the doubt regarding your connection knot,

which then strongly suggests frayed or nicked line, which is very common if you're negotiating heavy cover.

 

Roger