Can we use a messenger that does not alter the AI to solve the control problem? Instead of directly communicating with the AI, we would instead communicate with a messenger, who would relay our communications to the AI. The messenger would have no power to alter the AI's hardware or software in any way, or to communicate with anything or anyone, except relaying communications to and from the AI and humans asking questions. The messenger could be human, of a software bot. The primary job (and only reason) of the AI would be to act as a filter, not relaying any requests for release back, only the answer to the question asked. The ethics of this method are another debate. 

The AI would have to be physically isolated from all outside contact, other than 8 light sensors, and 8 LEDs. The messenger would operate 8 other LEDs, and receive information from 8 light sensors as well. Each AI light sensor would be hooked up to a single messenger controlled LED, and vice versa. Through this system, the two parties could communicate via flashes of light, and since there are 8, the flashes would signal characters in Unicode.
I would say no due to the possibility of psychological manipulation of the messenger by the AI. Also, the LED communication constraints place severe limitations on the capabilities of the AI, as the usefulness of AI is likely predicated on its ability to learn quickly from a vast amount of information (e.g. using the internet). 

In some sense you may successfully control an AI using techniques like this but the nuance of the control problem is controlling an AI without restricting its ability to solve our greatest problems. 

We already knew that we could keep an AI safe inside a computer isolated from the rest of the word, but the problem fundamentally is that we if had a truly general AI, we would never want to keep it isolated. Is there some way to unleash it so that it is fully capable of solving our problems while simultaneously making sure that it is safe?