Upgraded MinePeon 0.2.3a to cgminer 3.4.0, to see what happens next... 
Started @ 20:05 and @ 20:50, RPI rebooted. what USB hubs do you have connected?
an you disconnect all but one and see if it works with one then add more.
if they are different brands try the different ones to see if one is stable.
the Rpi reboots 2 times/day, and when it does i've to unplug it and the modem, plug in the modem and when its ready plug the Rpi
if i dont do this, the cgminer never starts again, because it cant find an IP, idk
if i'm not at home do to this, i lose mining time
I find with mine that when it boots up the ntpd sets the time. once that has happened if you restart the miners (click submit on the pools page) it seems to fix up the issues with the graphs and not seeing the devices Mh/s
Also mine ran overnight . so one now has 12 hours uptime and the second has about 7.5Hrs since I changed the hubs around.