Contour 2 Over-Night Update Issue

My Contour 2 system has begun acting quirky during the "over night" update sessions. The host receiver updates just fine but one or both of the two client receivers very often do not fully sync with the host (program guide and Contour menu will not display, last channel selected freezes, etc). However, if I call for a full connection reset via the Cox support toll free number, all three devices sucessfully reboot and sync just fine. Has an issue like this ever arisen before?