So using other than Minelab headphones on the CTX, is problematic it seems as the speaker does not disengage with the use of other brands of headphones. I'm using Sunray ProGolds and the way I got them to work without the internal speaker blasting at the same time is I use a 29 cent adapter from Radio Shack. Part #274-360. 1/4"female stereo X 1/4"male mono plug...Now it works on the ProGolds but I've tested it also with Grey Ghosts and Timberwolves and they work well too.. same results.....Should work with any other brands that use stereo end plugs. No need to open detector and add copper wire inside headphone adapter like some electronic mad scientists have done. This is a much simpler, smarter and cheaper way of solving the problem.