Siri on HomePod requires repeating requests multiple times to get a response.

I have had HomeKit with HomePods in my house for more than four years. But recently Siri on HomePod requires repeating requests multiple times to get a response. Over the past few months it has become increasingly difficult for Siri to respond to a simple request using the four HomePod minis in my house. Sometimes I must repeat the request four or five times to get Siri to respond. This is not due to background noise, poor annunciation, or the volume of my speech. It’s as if Siri does not hear “Hey Siri” or “Siri” until repeated multiple times. So what has caused this change with Siri?