I have no cold water supply at the valve that supplies water to the washing machine. It does appear there is some pressure in the line because it makes a brief pressure release noise when I open the valve. See link to videos below. The hot water supply at the valve works with no problem, for some reason there is no cold water coming out of the cold water supply line. I have tried disconnecting the washing machine hoses and cleaning the screens to the washing machine inlet valves. I have replaced the washing machine hoses from the black rubber ones to the stainless steel type to make sure they are not blocked. I have reversed the hot and cold washing machine hoses, to make sure there was not a problem with the washing machine cold water inlet valve. I have tried turning the main water supply line in the house off and draining the lowest pipe and then turning the water back on to try to clear a blockage in the line (this was done several times). I have taken apart (unscrewed) the cold water valve assembly fixture in the wall box as seen in the video above. There did not appear to be any blockage in the fixture itself. I don't hear or see any water leaking from a broken pipe in the wall somewhere. The washing machine is on the third floor of the house and the water line is on an inside wall. I do not suspect the line to be frozen. My next thought was to open up the drywall and further inspect the pipes and connections that are supplying the water to the hookup box in the wall behind the washing machine. Any ideas on what I should do next? Would it be worth it to unscrew the hot and cold valves in the box and reverse them, to see if the problem is the cold water arrestor/valve?