I got my ModMiner Quad working with cgminer yesterday (with cgminer running in an Ubuntu emulator on my Mac, had trouble getting it working directly on my Mac but this works for now).

Problem is that if I leave it running for just an hour or two - the following happens: https://gist.github.com/sanity/db5f4b7a4c2a85a133be

Note that all of the MMQs seem to have failed!  Any ideas what the problem is here?