HomePod Mini sound is dull and muddy. Is there an equalizer?

I own three HomePod Minis, and I am greatly disappointed by the sound quality. I don't expect any significant bass from such a small speaker, but I do expect decent quality highs and mids. I have reduced the bass in the Home settings, but the sound is still soft, dull and muddy with little definition or clarity.

Is there a third-party app or utility which I can use to equalise the sound differently?