Still seeing the problem, but haven't changed any difficulty settings yet. Also, running cgminer 3.1.1
I ran a test mining at difficulty 32 with 14 Mhash and didn't see these disconnections. I am noticing that users reporting it are running cgminer 3.1.x. I'm running 2.11.x. I'll do some testing with the newer version. Perhaps there's some difference in how they're dealing with stratum.
I can confirm that I get this with cgminer 3.1.1 but not 2.11.0. I'm attempting to find out what it's doing differently.