After four years, I can say with certainty that my RCN cable modem service fails ONLY on cold days due to low signal level. When I remove the splitter and connect the modem directly to the wall jack, the signal returns. If I leave the splitter in but remove the connected TV and VCR, I still get dropout.
My annual December-or-January interaction with RCN goes like this: They send a technician, who replaces the modem... on a warm day when there's no dropout anyway. Or they suggest that I replace my splitter. Whatever is done, there's a few more occurrences of dropout on cold days. Then, mysteriously, the problem goes away -- for the rest of the winter. I can only conclude that RCN adjusts something in its system...without telling me about it. Do I guess correctly? I need to know; it would help me in negotiating with them.
-- Charles Packer