I have a Privia 330 keyboard that seems to work well. I have a Behringer UB2442fx-Pro that also works well.

When I plug the keyboard into the Mixer with a 1/4 inch jack, I get no sound. If I plug the wire directly into a speaker it is fine. If I plug a guitar into the same input, it works fine... so I know it isn't a wire issue or an issue with either piece of equipment. I tried stereo and mono jacks. I even tried using the headphone out.. same issue.

If I plug into the aux return, it works fine... but that isn't where it should go.

This is driving me nuts. Does anyone have any idea? I am guessing there is some impedence mismatch... but this mixer should account for that I thought.

Please advise.