Headphone stereo problem

I mostly use the kemper with a power amp and 4x12 cab. I want to try it with headphones but cannot get sound to both ears so probably not set up correctly for stereo or whatever. Any clues on how to do this would be helpful. It is probably simple but I dont know how to interpret the kemper menus and nothing seems to work. Thanks

What good is space option if I can only hear one ear of headset???

Anyone home....not gonna get an easier than this question.

Apparently the older Grado 60 headphones has an adapter with 2 black rings and my be preventing stereo.

No have not. Trying to find another source.

the headphones are bad....): thanks