It is not always a calcium or pH imbalance that causes slimeyness. Sometimes, there are proteolytic, halophilic (salt-loving) yeasts and bacteria that will break up the cheese and cause softness on the surface. At times, the salt itself carries these microorganisms. For example, some halophilic lactobacilli naturally exist in brines, as do halobacter, serratia, and similar species. If what you are doing isn't over, start over with a minimalist approach and eliminate each variable until it works.
