Jek,
Try reaching out to Danny at GR Research. Gary Dodd was a personal friend of Danny. He may be able to give you some direction on how to fix your problem.
Dodd PreAmp batteries not charging
Please help, my Dodd pre received new batteries last year which powered my preamp nearly all day long, now the batteries only last about 20 to 30 minutes. I exchanged chargers with a Dodd phono pre but without any results. Could the batteries need replacing this soon? I usually listen to my system 5 hours. Week. Any input is appreciated