R/O water smells skunky

[lastlight]

Anything higher than 5 and I replace the membrane. Burns the resin so fast at that point. My incoming seems to be around 200. I flush for a few minutes then run the unit but bypass the resin until the membrane outputs less than 5. Prefilters I replace maybe twice a year. I back flush before and after using the unit. A membrane lasts me about a year but I make very little water now it should last longer.