Also, I wanted to confirm what was mentioned earlier in the forum.  Setting the frequency to 1000 and the "auto-frequent" to "1" in the JSON file has greatly improved my stability and hash rate.  I have no idea why that would be the case, but it is working much better now.  Been running about 18 hours with no hiccups at 6.85 gh/s.

So it may not work for everyone, but I have seen a noticeable improvement.