Hello ADmrkynk,
Thanks for posting in Apple Support Communities. Are you playing Spotify using AirPlay? If so, do other audio apps work without any issues or does the same thing occur? Test with another music app to see what happens as that will help isolate whether the issue is app related or HomePod.
If this happens with AirPlay and only Spotify is impacted, try the steps in If an app on your iPhone or iPad stops responding, closes unexpectedly, or won’t open - Apple Support on your paired iOS device. This should resolve issues with the third-party app.
If it happens with other apps, the guidance from If HomePod mini or HomePod isn't responding - Apple Support may be helpful in identifying the issue although the title of the article is a slightly different issue.
Best regards.