even audio power amplifiers don't have to be perfectly settled at 0V. anything below 100mV is usually ok, and doesn't produce a turn-on thump. the only time offset needs to be tightly controlled is if the circuit is used for measurement, and depending on the application, even then some small value of offset is allowable. now if you are driving a multiplier as an RF modulator, there's an application where any DC is generally unacceptable, because it causes RF leakage through the modulator.