I'm developing a multi channel amplifer using TAS3251, and I have a problem with internal voltage regulator (pin 23 - AVDD). As described in the datasheet I've put a 1uF bypass ceramic capacitor to GND but the voltage on this pin is about 7.5V with superimposed a ripple of 1V peak-to-peak at about 4kHz frequency. It is normal a such ripple?