We recently had a pair of McIntosh MAC4300V in for repairs at Bob the Tech Audio. Both of these units were behaving oddly, front panel controls were not working. Sometimes they would power on or take other actions by themselves, and the remote controls were not working. Both required switch disassembly and cleaning. This resolved much of the front panel and remote control issues, and the odd behavior. We disassembled and cleaned the speaker relays on the one unit as the speaker outputs were a bit intermittent and noisy as well.
One of the units had some additional issues. One faulty logic device had one of the audio inputs enabled all of the time, even when other inputs were selected. Another logic issue in this unit was the lockout function which disables the rear panel remote control was enabled all of the time. The front panel indicator LED was lit, and the pushbutton had no effect. The more interesting part of this latter issue was that the newer date code replacement parts were not working in the circuit as it is designed. We analyzed what was happening and modified the circuit slightly so that the new parts worked. Once complete we had fully reliable front panel and remote control operation.
Lastly, we aligned the AM and FM tuners in the MAC4300V using our Panasonic 8122 AM/FM generator. Tuner performance is quite good in the MAC4300V.
For your McIntosh MAC4300V repairs, or just to have your tuner aligned, contact Bob the Tech Audio.
