Try attenuating with electrolytic capacitors. .01 -.1-.47-10-47 uf 50 volt are cheap. Need to go as near to the source as practical. I cheated inside the BORG with tantalum because of size/fit limits. Schmucker, really has some issues these days. I suspect everything has been outsourced and from designer to screw tightener the far east crew has never gotten near a genuine battery. Unbelievable what I've seen...gimmee a break button rectifiers pressure sandwiched between to aluminum sheet metal plates?
Try the caps and maybe you'll slide on this one.