HDMI port not working

My HDMI port used to work find but lately it started to lose connectivity and i would have to move the cord around the port to get a signal.  Now it does not come on at all.  I tested the cord and the TV with other working things so I know its the port.  Dell customer support keep trying to tell me that It was a setting on my tv and he was being very mean about it.  The port sometimes will work for a second if i hold the cord steady but I think I have a lose connection from the HDMI port to the motherboard. Any recommendations would be good.