I have been asked to accompany a team of attorney's to a site where someone died. Both attorney teams will be present and in our initial agreement it has been agreed that i can shoot video but that I cannot record the audio. i am not using anything fancy... i have either a kodak zi8 (basically an iphone) or a canon vixia hf11. obviously those both have on board mics... i will have to show the opposing team of attorneys that i am not recording audio... any advice?