Ubuntu Forcing HDMI Output on Boot if Monitor disconnected

I have a ubuntu 14.04 server that connects to a A/V Amplifier via HDMI. The problem is, if the amp has a source selected other than the Ubuntu during boot up of the ubuntu m/c, then when the ubu server source is selected there is no output. This is the output of xrandr when the m/c IS selected as the A/V source during bootup: xrandr -d :0 Screen 0: minimum 320 x 200, current 1600 x 1200, maximum 16384 x 16384 DFP1 disconnected (normal left inverted right x axis y axis) DFP2 disconnected (normal left inverted right x axis y axis) DFP3 disconnected (normal left inverted right x axis y axis) DFP4 disconnected (normal left inverted right x axis y axis) DFP5 connected 1920x1080+0+0 (normal left inverted right x axis y axis) 160mm x 90mm 1920x1080 60.0*+ 50.0 59.9 60.1 50.0 30.0 25.0 24.0 60.0 30.0 24.0 1776x1000 50.0 59.9 50.0 25.0 24.0 60.0 30.0 DFP6 disconnected (normal left inverted right x axis y axis) CRT1 disconnected (normal left inverted right x axis y axis) I have tried executing a xrandr script with CRON during boot, however that does not work: @reboot /usr/bin/xrandr -d :0 --addmode DFP5 1920x1080; /usr/bin/xrandr -d :0 --output DFP5 --mode 1920x1080; I also tried modifying the kernel params in /etc/default/grub.conf: GRUB_CMDLINE_LINUX_DEFAULT="video=HDMI-A-1:1920x1080D" GRUB_CMDLINE_LINUX_DEFAULT="video=HDMI-A:1920x1080D" I tried both HDMI-A and HDMI-A-1 as I see that others have used that ID, but neither work. After rebooting with the server NOT selected as the A/V source, and running xrandr it appears that CRT is enabled, but not the HDMI Source: # xrandr -d :0 Screen 0: minimum 320 x 200, current 1600 x 1200, maximum 16384 x 16384 DFP1 disconnected (normal left inverted right x axis y axis) DFP2 disconnected (normal left inverted right x axis y axis) DFP3 disconnected (normal left inverted right x axis y axis) DFP4 disconnected (normal left inverted right x axis y axis) DFP5 disconnected (normal left inverted right x axis y axis) DFP6 disconnected (normal left inverted right x axis y axis) CRT1 connected 1600x1200+0+0 (normal left inverted right x axis y axis) 0mm x 0mm 1600x1200 60.0*+ 1400x1050 60.0 How can I force the HDMI to be enabled and connected during boot, irregardless of whether or not it detects a monitor ?