Recent increase in volume (magnitude and step size) for Google media_player devices

I’m not having luck finding anyone else with the same issue, or really even where to post such a query. My apologies if I’ve missed something.

Recently I’ve noticed that a number of automations using the spotcast HACS integration and various Google media_player devices have become perceptibly louder for the same volume level. I have a number of automations that smoothly fade volume in and out to/from predefined levels on different devices (old Google Home speaker, a Google Nest display, and a brand new Google Home Mini), and I have noticed two things:

  • Former volume level in the neighbourhood of setting 0.25 is now reached at the much lower setting of ~0.1
  • Step size 0.01 was formerly not perceptible (even close to zero) but is now obvious

I’m not sure exactly when this happened, but I think about a week ago. I was triggered to this finding when the fading lullaby automation in my son’s room became unusably loud. This was around the time that I updated my HassOS from 2023.2.4 to 2023.3.1, so I tried downgrading but that had no effect. The behaviour seems to occur in the same way regardless of what the input audio source is (i.e. using the spotcast HACS integration, casting from the Spotify app on my phone, or playing a local audio file, all the while making volume changes using the media_player.set_volume service), however I had never checked this with a local audio file before so it is hard to say for certain. My Sonos home theatre system seems to be unaffected.

Has anyone else noticed something similar with Spotcast, Google media_player devices, or others? I’m not sure where to start poking around to narrow down possible root causes. My gut feeling is this is something on Google or Spotify’s end, but not sure how to check that hypothesis either. For now I’ve significantly reduced all volume settings in my automations, but especially the step from 0.01 to 0 in a quiet room is abrupt whereas I really couldn’t detect it beforehand.