Help Voice dialer popping up when connecting to headphone jack

Bought a cheapo .8 to .8 cable so I can listen to Pandora through a shelf stereo with an aux in. Everytime I plug it in I get a prompt to voice dial. I sometimes get the icon that is just headphones, and sometimes get the full headset one. Often if i just touch the phone while it is playing that same prompt pops up. Can't find anything in settings to disable this. Is it my crap cable? Any ideas?