I sometimes use my Raspberry Pi OSMC install on an HDMI TV and sometimes on an older set with composite video phonos. there are many posts about disbling teh HMDI output. Having just read the definitions (https://www.raspberrypi.org/documentation/configuration/config-txt/video.md) of 
**hdmi_force_hotplug** and **hdmi_ignore_hotplug**, it looks like I can force video output either to TRRS (on the 2.5mm jack) or HDMI.

I wonder: is it possible to send output to TRRS, unless HDMI is detected, in which case, HDMI should be used?

Thanks.