U3415W, Menu capacitive button not working

For a while now the menu capacitive button is not working on the U3415W. The other buttons continue to work but I can not bring up the Menu. The third button from the power button brings up the Input choices, I can move among the choices but I cannot use the check to select. Is there a way to change my input function without using the button through the computer? I added the DELL software but cannot find that option?  I currently can only use mDP but would like to be able to switch to HDMI to monitor another computer.

Very frustrating and I am out of warranty.