All of my headphones have very low volume. RAT phones, KILLER BEES, and JOLLY Rogers. All of these have a mono/stereo switch, (the RAT phones, you just have to flip the cable.)
Anyway, I spent my first hour searching for targets in my back yard without headphones, as I thought all of my headphones were bad.
Late in the evening, I did a generic google search for issues with headphones and the Nokta Simplex. Found multiple posts about this. But also, within the same threads, posts with zero issues. I read one post, where the person slowly inserted either the headphone plug, or the headphone adapter to find the ''sweet' spot of volume. I must do the same.
I must continue to search for a real fix for this, without having to send my machine back. Its prolly the little headphone adapter.
BTW, I haven't been visiting or posting on metal detecting forums for a few years, but when the price of this Nokta Simplex, videos, and when a buddy of mine got his, I just had to see for myself. So yeah, I'm back.
ejf