YES! I've been getting the same reports from my visitors since Friday 4/23. I have seen very little about this, so it appears Google isn't aware of the issue. So I have blocked all 3rd party networds on Adsense for now (102 of them!). I don't know yet if this will temporarily solve the issue.
I'd sure like to hear directly from Google on what they're doing about this, and an ETA when it will be fixed.