Just moved in and prior homeowner had a 6 zone mzc 66 setup, all speakers and wall controls seem to be intact..... 66 unit powers up and then....nothing...prior homeowner said he had replaced the unit twice since 08 and gave up on it. The wall keypads look outdated......what is an "easy" swap or update that wont break me? There are currently 5 zones with two speakers each, 4 sets in ceiling of different rooms and two speakers outdoor around deck. Any help appreciated.