Is there a way to make the headphone out mono?

[Gre404]

I've got edrums split into left and right but it throws me off to hear the kick on one side and the rest on another. I'm used to hearing them all in both ears. Is there any way to do this in the settings? I tried one of those plugs that connects the left and right in the plug but that makes the sound smaller and flat. I have a little mixer that can do this but I'm traveling on train with a bunch of other gear and with the mixers big transformer it's a bulky thing just for this. Leaving in some hours so don't have time to order some smaller thing for now. Thanks for any tips