Problem solved. It isn't the Cary after all. For some reason, when I push the Eichmann bullet plug all the way in on the left channel of the DNA-125 the channel drops. When I pull the plug out a couple millimeters everything is fine.
Thanks for your idea, Jon! Next time around it could be a tube, and I'll know to check it.
Thanks for your idea, Jon! Next time around it could be a tube, and I'll know to check it.