I bought a cheapish 1/4 to 1/4 10ft extension cable from Guitar Center, the brand is Hosa, to pair with my Grado's 325is.  But, when I move around while connected I lose sound from one channel or the other or all together.  When I place the jack into the ext cable it wiggles without much...

I am going to break audio equipment into three categories that I simply made up. The precise line that separates these categories is really unimportant and not the point of my post.      Consumer (TV speakers. Apple headphones, Sub $20 headphones)   Consumer Pro ($100 Headphones...