Is normalling audio between headphones 1u, mixup and palette via 3pin cable possible?

As the title says. I’m asking for a friend if the following is possible: jack >headphone 1u> mixup chain in, then hook up the mixup chain out to the jack on the palette case. Would that work or is not possible and he better use the palette’s buff mult to route the audio to the headphone and mixup? Thank you

No, the Headphones 1U rear jumper is an input not an output, so this would not work as you describe.

I see, so would it work with an y 3 pin cable? like the one used in desktop pc to split fan power

mixup chain out>y cable>headphones and palette

the goal is to have the same audio signal available in both the output jacks on the palette and the headphone module

I keep hoping for a way to have it work like a mixer where the outputs work and the headphone out works all at the same time internally. Maybe if you connect the MIXUP to the case with the 3-pin and take the output jacks of the MIXUP into the HEADPHONE 1U it’ll give you the option…?