I have used a PAV/PDSD pair for a number of years without incident. The PAV recently did have a power supply problem that was repaired locally. They also replaced a number of caps that were leaking, returning the unit to pristine sound. The PAV does get surprisingly warm, so needs good ventilation. I would not stack the units, no matter how neat that might look. I have another PAV that I've used for decades, and it also gets very warm, so I suspect it's endemic to the design. I use my pair for both music and HT -- they do produce fine sound.
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