Power in to Paula is close to 5v, and very stable. I also did not detect any leaking/bulged capacitors.
Is Paula really dead, or can something else be at fault?
Sounds like you lost the -12V rail. The amplifiers (and presumably DAC) require a split power supply. Very little else depends on this (possibly the RS232 output, but that might be implemented differently), so if you lose it, your audio will clip whenever the waveform goes negative and you may have serial port problems too.
