Optiplex 3040 Dual monitors not working properly

Small form factor

Windows 7

I have two monitors. one plugged into the HDMI port and one plugged into the Display port.

When the computer is rebooted, or goes to sleep, the monitor in the HDMI port does not come back on unless I physically unplug the cable from the back of the machine and plug it back in.  My user is in a wheelchair and this obviously isn't practical. 

If it is the only one plugged in, it works, but if they are both plugged in, it does not?

I have updated the latest BIOS and all drivers and windows updates.

Please help.   Thank you in advance.