HomePods playing the wrong song.

My HomePods have started to play completely the wrong song when requesting something via Siri.

For example - "Hey Siri, play the album xyz by abc"... Siri will say "now play the album xyzzy by abc" and then plays something completely different.

I don't subscribe to Apple Music and don't want to... I've bought many albums via iTunes over the years and up until recently it's played them on request no problem...

Interestingly - regardless of what song I request, it will often start playing an artist or song beginning with 'A' and then continues to play songs in alphabetical order...

Has anyone else experienced this or found a solution? It's driving me slightly crazy.

Many thanks.