Hi
Same thing happened to me, it used to work so I am wondering if an update killed it. i am trying to remember when it worked and I think it worked in the original 10.5
by 10.5.20 it didn't no matter what i did. i thought it was the unit but like you i hear it click
it def worked in all of the 10 ones
i have 11 now an it still doesn't work so i actually took it out