Ok sure verbal commands are not going to work in every situation during combat but it is a option that should not ignored .And there are ways to make it more secure such as over your comlink. if the order does not come form your com then its ignored. to spoof you commands using voice the enemy will have to hack your link then use magic or cyberwear to spoof your voice.
Core pg 242, Snoop
This action lets you intercept Matrix traffic sent to and from your target for as long as you have the target marked. You can listen to, view, or read this data live, or you can save it for later playback/viewing if you have something to store it on (your deck will do).
First off, both the Rigger's Commlink, and the Commlink you give to the drone (since you turned off its built in wireless it will need a separate Commlink) will have to be online. Which means they can be found and hacked.
So... Hack one of those Commlinks, and Snoop on the convo to record your voice giving commands. Since the commands have to be short, you're probably just shouting "Protect our Decker Tony" or "Geek the enemy Mage" or something. Then while I'm recording your voice over and over, I make a soundboard. Then while I've hacked the drone's Commlink, I change the Address Book entry so when my Commlink calls the drone, it says "Mr Rigger" instead. Since the drone isn't actually plugged into the Commlink (you wanted to prevent the drone itself getting hacked, remember?) then all it has to identify the caller is what the Commlink tells it. Now when I call, the drone thinks it's you. Then I use the soundboard to build new phrases like "Geek our Decker Tony" or "Protect the enemy Mage" and watch the drone go to work.
You can probably precede a verbal command with a rotating cypher word, to keeps others from trying to hijack the drone by imitating you, but it would probably require GM adjudication.
My Missions character has a Smart Firing Platform with wireless removed. He commands it verbally, preceding each command with a rotating codeword that changes with every command. It is programmed to ignore any command not preceded by the expected codeword.
-k
Just curious, but is your rotating cipher actually a rotating cipher, such that you have to keep an AR window open showing you the proper word at the proper time? Or are you just using a memorized phrase?
Cus if you're displaying the next word to yourself, then I hack your Eyeware and watch the feed too.
If you're using a phrase, it's probably going to be a simple phrase that I might know too. "Mary, shoot that guy. Had, now that one. A, watch your back. Little, go for the head." ... "Lamb, shoot your boss!"