Miele 1/2 tabs not cleaning as well as they had been?
I have noticed of late, that stuff isn't necessarily coming out quite as clean as it had been using the 1/2 Miele tabs. Glasses sometimes come out of the DW with a little schmutz or a "greasy" film (especially if the glasses went into the DW all fingerprinted up--like they are when we are eating buffalo wings!). Flatware and dishes too have the occasional schmutz more often than I recall happening before. I haven't gotten a new box of tablets in a while, so that hasn't changed. I cut up a bunch at once, and store them in a pint deli container with a closed lid. Do the tablets degrade, or lose effectiveness over time? Do they have a "best by" date???
I ran a sani-cycle, and used the Miele DW conditoner recently, but I'm not sure it made a difference. I have used full tabs in a few recent cycles (esp if very full, or extra grimy), and I think the glasses came out "squeakier" clean than they have been in recent 1/2 tab cycles (prior to this, they came out perfectly shiny and clean using the 1/2 tabs).
Any thoughts from the Miele/Miele tabs gurus before I call Miele?