Turn signals don’t work when headlights are on

Hello everyone!
69 dart gts, 340- 4 speed:
Turn signals don’t work when the headlights are ON. They do work when the headlights are OFF, although, left is a bit slower. I’ve cleaned the fuse contacts, replaced all the fuses, replaced the emergency flasher switch and had pulled the headlight switch. I have power at B1 & B2 in the headlights switch. I plan on pulling the cluster out and trying to poke and clean around there too. I’ve dug around on FABO A lot but couldn’t find this specific problem. Any help would be appreciated! Thanks!!