Two possibly related Maestro only problems:
- Disconnecting the AC power (with a connected bay battery) forces a drop of radio connection. i.e. a mains failure disconnects the radio. It will reconnect OK
- As soon as the radio connects the Maestro speaker and phones connection starts with a combination of, fairly loud, background buzz with overlaid crackle. No controls will affect the sound (AF/AGT/RX/TX/etc). Then it may stop and normal operation starts.