Took your advice and after the plumbing guy took 15 minutes browsing through the myriad of adapters, we came up with a brass hose barb connection. The barb end pushed into the hose and the other end was a female end, so we got a 3/8" male to female adapter and it worked like a charm. The original plastic fittings (some kind of ferrule nut with a slip ring thats only designed to go one once and not come off) were poorly designed and made. Upgrading to brass proved to be a much better fitting. I'm not sure how long metal to plastic will last but I suspect many years.