[Elecraft] Hum using K3 with Behringer Xenyx 808 Mixer

[Phillip Zminda]

I have been using a Behringer Xenyx 808 Mixer with my K3 in order to share headphone and powered speakers with other devices. When I connect the K3 audio output to any of the balanced inputs or CD input jacks on the mixer I get a very significant hum. I can overcome it with higher audio settings but it is particularly annoying with headphones and I really want to fix it. I have run a jumper from one of the chassis screws on the mixer to the K3 ground terminal, switched cables and inputs, changed AC sources on the mixer power supply and the K3 power supply and it still won’t go away. It doesn’t seem to be noticeable from other sources when I disconnect the K3. The mixer power cord is a 2 wire but can’t change that. Anyone using a mixer that can help me fix this problem? I would rather not have to disassemble the mixer if I can avoid it. Is there another device I could use for sharing audio that might work better?

Thanks,

Phil N3ZP