Got tired of my headphone cable running over my keyboard to my audio interface, so I took a 1/4" TRS cable with a right angle jack and cut off the other end and wired it to a female TRS jack. 

I then designed a simple mount, the angle of matches the sit-stand desk control panel, that allows the headphone jack to screw though the front plate and has 2 holes to screw the mount to the bottom of a surface.

Does not require supports, print at default orientation.

Somewhat flimsy when plugging or unplugging. Will usually be plugged in but I may make a version 2 that is more stable and includes tension relief