Yup, been there. Playin a show once and my Dunlop lock on the upper horn's strap side let go, bass came within an inch of hitting the floor when I caught it. There's a Warwick recessed straplock in the upper horn, but it was the ball bearing mechanism that failed, which I guess is pretty common.
I've been using Dunlop Dual Design straplocks on all my basses from day one, and I like them most because they spin smoothly 360 degrees for comfort live and (for the most part) hold pretty solid. You just need to be sure to replace them every couple of years (the strap part, not the button on the bass itself) because the ball bearings will weaken.
I've seen a lot of bassists actually use electric tape on the upper horn to hold their strap on to prevent it. LOL, I guess depending on the type of music you play and your band's image this look might fit, but I could never stomach putting tape on my basses. Especially when new straplocks are like $12!
Good luck all of you with your DAMN STRAPLOCKS and if anyone wants any advice on recessing external straplocks into their Warwicks or relocating the button a little higher on the bridge side, send me a message. I've been doing that a while and have some helpful hints. : )
Andy
living.syndication