To be honest, I noticed after few days now that I dont think zm is the reason. Its more caused by the Windows update that messes up mining. My most stable rig is also bananas now.
Why don't you just switch off MS updates? Really, the only reasonable update from MS was to 1607 (fixed ETH 3Mh/s). All others didn't affect mining at all or made it worse...
Its switched off, this security update was forced on. There are multiple reports about it, read around willya.