First time I've ever seen the 16 ohm version of these--sounds like one may have issues. I see they're Altec diaphragms from 1979 (date code), are those the original 16 ohm diaphragms? I zoomed in on the one photo and flipped it upside down--diaphragm part number is 16 54 34117......
Altec 802-16g For Sale | AudiogoN