I had a 2000 MIM Jazz 5-string that I would struggle with every great once and a while to make the B string sound solid (Those are 34" basses and while not premier basses, not cheap, either).
Once I made sure there were no twist in the B string, the witness points at the bridge and the nut were set, and the winding was all the way down to the base of the tuning post (making for a good angle across the nut), the B string would sound pretty good. It is my belief that just a little neck relief was helpful, but I could be dreaming on that one. And again, not swearing to this, but an ever-so-slightly higher-than-usual action could help, too. And I use Ernie Ball Power Slinkies with a .135-gauge B string. That just happens to be what I'm used to playing.
I don't have that bass anymore, but I do have a 35" Mike Lull M5V and a 34" MM Stingray SR5. Following the same practices above, the B strings on both basses sound great to me. I even have a Hipshot Drop-tuner on both basses. The Low A works really well on the Mike Lull, and decently enough on the SR5, if I don't hit the string too hard.
This is an exercise in seeing what works for you and your bass. You'll see all kinds of ideas and solutions that people rightly swear by, but may not be the ticket for you. It won't be for a lack of ideas...