just wanted to add .02 that i as well have 2-3 original Msr dromedary bags. And a paddling partner and myself experienced the same issues. After a number of days the water tasted and smelled off.
Couple years back I contacted Msr and of course they denied any other complaints. And really had no solution or advice. And I have never used the bags again
But what I was told from some people was that it was the chorine or the bromate in the water reacting with the liner. I haven’t gone any further to experiment with using filter water to see if that had a effect on the smell/taste.
I would assume a reverse osmosis system or a carbon filter cartridge would be required. Previously in the past I had a water company come and test my water and told my fridge water filtration was a joke. Unfortunately for this salesman he tested the single stage carbon system on the fridge and it was perfect. Sales pitch destroyed
So i have never taken it further to see if using a carbon filter on the tap would resolve this issue. But looking online some of these filters are as low as 13.00 just have to add fittings.
thank you for posting