Thanks for the comments!
I have tried all of the above, should straps as low as they can go and in between, waist as tight as it allows me etc. Even if I drop some weight pack still seems to slip. I'm comparing with my 12year basic canvas pack which does not slip but I don't want to go back...
I have a SG 40/56 + evo frame and when I load the bag to around 50kg the bag drops and the lumbar pad sits below the small of my back ie, not in my lumbar area. I have the medium waist belt and cinched it as tight as it allows me. I can get my fingers easily under the should straps so most of...