You are not alone. Randall May is really not good quality hardware and there is a reason all the companies that use them no longer do (after getting out of really really really bad contracts). My suggestion if possible would be to replace them with another brand of stands and carriers if possible. Thats easy to do with some instruments like basses, but a a bit trickier with tenors and even some snares. Just know that all marching stands take a beating and will degrade faster than concerts stands. It's inevitable. If buying new stuff isn't possible, you can try to reach out to schools that have old stands and see if you can get replacement parts from them. Sometimes you can get lucky and find something that will work at a hardware store, but the stands are designed to have specialty parts so you have to go through Randall May. Randall May is the reason I've never considered a Yamaha line since I've been teaching (I personally used Yamaha in HS and College). Would strongly consider now though since Yamaha is making their own hardware it is looks pretty good when I saw it at TMEA.