I think that happened to me as well, rather rarely and I considered that to be a bug of Spotify, not the FP, as I have bugs different and changing when using Spotify since years, for me the usability of the Android App detoriates since years.
However you might want to check battery optamization settings of the app and if any battery saver is enabled when it happens.
Edit: seeing your other topic I’m rather wondering if its the same and/or connected