Sound quality issues

[Hirsch2k]

Plan

Premium

Device

Various 

Operating System

Android 7.1 /8.1

My Question or Issue

 Hi,

I have issues with my sound quality recently. It seems to have started ~8 months ago, when there was a fourth quality setting introduced.

I use an Android TV Box into an DAC and Headphones as well as my phone (Redmi Note 4). Both use the newest Spotify versions from the play store. I have this issue on both devices across a range of headphones.

The sound is "bubbly", especially in quiet passages. It sounds similar to 96kbps MP3. This happens on tracks I heard dozens of times before and would have definitely noticed if this was in the recording before.

Example from 03:20 - 03:30 

Disclaimer: Its likely that the effect won't be noticeable on cheap equipment (no bragging intended)

Streaming quality is set to the highest setting. No EQ or effects are active. Data saver is disabled. Gapless playback is disabled. I tried deleting the cache as well as reinstalling the app.

If I set the quality to lowest I notice a further degradation of fidelity. So the quality slider should have an effect.

 Edit: I checked with several .flac files if my chain or hearing is flawed but they play as expected 

Is there a way to find out by the size of the cached files which quality level is actually streaming maybe?

Edit:ok I inspected the cache after Deleting it. I found 2 Files in there big enough to be audio files. Assuming that spotify loads the track playing and the next into cache i calculated the bitrate of the files in cache and both turned out to be 280kbps which seems ok for highest quality settings.