So i pulled out and tested the two voltage regulators in question and they both tested fine. I re soldered them in and got audio for about 2 seconds in pure direct mode but then it cut out. I am running through the service manual right now going through the diagnostics and found that, Communication and bus line connection between microprocessor (IC83) and DSP (IC921). it gave me a DSP BUS error telling me the communication between those two items is failing. Does this seem like a case where i would need a new logic board?