Salter Labs Water Bottles

Does anyone else have this problem? It seems that one out of every few bottles seems to last only a couple days before they start leaking air from the pressure relief valve! I treat all my bottles in the same way as far as cleaning and filling, but it doesn't seem to make a difference. I use 2 bottles at a time, rotating the bottles so one bottle gets used every other day. I have to do it that way because my lungs are pretty bad and I don't have the luxury of just disconnecting the same bottle and go fill it up.

I try to make them last 2 months that way so it's about the same as using a bottle a month, but lately, with them going bad, I end up not getting a consistent good flow of oxygen all the time and it wears me down.

I hate not having the water bottles because the humidity keeps my lungs moist in order to cough up the phlegm more easily. I feel like I'm in a desert without it.

Has any of you guys had the same problem?