zeni7 I see no resolve so maybe you still have this trouble.
Definitively you have agressive memory timings. I also push my memory out of bounds until I get a BSD during crunching and then I throttle back until I have 24 hours running no problem and keep it like that.
My devices are setup in a way that if a BSD due to memory fault happens it will restart all again and continue crunching. If I am not to monitor, this machine will BSD repeatedly and give the impression that it is crunching but with low results. I had this a short while ago when I fired up a new rig, a low point count made me check and monitor closely the machine and I had to throttle a little some memory settings.
A good test is to go through Prime95 or even the Boinc benchmark done three to four times in a row can BSD once if you are too limit.

In your case you say that you have longer times but your daily point count is it higher or lower. If higher BSD theory is wrong, lower then it could be the culprit.