Trouble with decaf K cups

[Psychodisney]

I ordered several boxes of K cups a couple of weeks ago and for some reason the entire cup of water isn't coming through. All of the offenders are decaf. The regular flavors dispense the full cup but the decaf gives me about half. I descaled the machine last week thinking maybe that was it....but it didn't help. Anybody else have this problaem or a solution?