Normally, a magazine with a #5 on the followers can only use a #5 follower and newer magazines use a newer follower. I'm wondering if someone replaced your followers with the wrong ones but I don't know how to tell. You might consider calling Glock at (770) 432-1202. Give them the serial number of your pistol and ask if the magazines that came with it should have #5 followers (you may have to explain the problem and that it doesn't happen with a new mag).
Part numbers for you (high capacity magazines)
Follower for #5 and earlier - SP 01028-5
Follower for #6 and later - SP 01028-9
Spring 11 coil - 2551
Spring 10 coil - older mags (do not use with tac lights) 448
I would just go with the 11 coil springs. Also, per Cohland's #30 post, measure the opening to be sure it's in spec 9.4-9.6mm.