Yes, I fully agree. This has been my ongoing experience tooi.
Why I think this happens is because there might be two compilers, possible on different machines, obviously NOT instances of the same compiler and depending on where you request is picked up it either is complied by a good compiler or a bad one.
What @Kodular should do is get a bunch of techs on standby, give the public a notice that they will be bringing down the build server for how ever long, bring it down. Strip them of ALL compilers and redeploy ONLY THE GOOD, TESTED ONE.