There are many multi-room audio systems on the market that are designed to accomplish exactly what you are looking for. You can install keypads or touch screens in each room along with speakers. The most basic type of system will allow you to have four sources. Sources are items like a radio tuner, CD changer, or music server. The keypads will also allow you to turn rooms on and off and even turn the entire house on or off. More elaborate systems can control lights, heating/air conditioning, your pool equipment, or cameras. Each room in these types of systems can play any source at any time, totally independent. One room can play a CD and the other can play the radio. Depending on the system you can even control the sources. You can change radio stations or CD tracks no problem.