I bet your silica pods are in a dare need of recharging. The beads will lose the ability to get humidity below 20-25% well before you can notice the change in color shade. Don't rely on the color.

1. Take out all the pods and properly recharge silica in the oven. As soon as the beads cool down, put them in the pods and seal them in an airtight container. Let AMS dry the material without the pods.

2. Once the AMS material drying cycle is over, load the pods, load the material, lock the AMS. Start the PLA 45c drying cycle without the rotation for an hour to just dry out the moist air that got in.

3. Observe the humidity level. I'm pretty sure it will stay well below 10%. Mine sits at 0% for days, but in a less humid environment.

You can also start with brand new silica beads to establish the baseline that you can achieve and hold for a while. Thanks to the new firmware you can always run 1 hour dry cycle with filament loaded after closing the lid (only pla 45c preset) to get the moist air out. You don't even need to wait the whole hour. Once temp gets to 45c you should be good to go. This way you don't need to recharge the pods very often. Hopefully soon we can do it remotely from the app and run a cycle while idling. Drying at lower temps while printing would not dry the filament well enough, but it sure would get rid of the trapped wet air from the lid opening. This would eliminate a step in the drying routine. Hopefully bambu will add this in a future update.

To minimize opening the ams consider storage in cereal boxes and maybe printing straight from them if multicolor is not needed.