Please check out a thread I did , [link]http://www.rcuniverse.com/forum/I_must_touch_Tx_arial_for_my_AFP_to_work_%21%21_he lp/m_1998510/tm.htm[/link] cause you are having exactly the same problem that i had, but instead of touching the front panel as you are doing, i had to touch the arial.

What I finally did, which is what probably solved my problem, (and not the notch or aluminum foil) was I changed the shielded wire to a thicker and much better shielded one. If you do not have any experience with soldering, give the job to someone who does, not that its a difficult but better avoid frying your interface. Beleive me there is nothing to worry about, the interface is fine, its just the piece of wire.