Poor sound quality on one of my devices

[snyhamn]

Device

Asus Zenfone 6

Operating System

Android 10

I have an issue with the sound quality of Spotify on my new phone, an Asus Zenfone 6. Even though sound quality is set to very high it is still very poor. When I connect the same headset to my old phone, a Zenfone 5, or any other device set to very high, the quality is noticeably better. Equaliser is the same on both phones, and I have tried to reinstall the app and clear caches several times. 

Regardless of quality being displayed as very high, it seems the quality is always on low on the Zenfone 6, as it sounds the same as low quality setting on any other device.

[Mikawo56]

Plan

Premium

Country

Belgium

Device

Old phone : Huawei P10 Lite / New phone : Nokia 7.2

Operating System

Old phone : Android 8 / New phone : Android 10

My Question or Issue

I have exactly the same problem with my new phone. I've done the same operations as snyhamn: I tried to clear the cache, to reinstall the Spotify app,... but without success. Same thing with a factory reset.
The strange thing is that in very rare cases, if I kill the Spotify process and restart the app, 1-2 songs will play in high quality before the problem returns.
On my old phone, I don't have that problem.

I have also just found this topic, which I think also describes the same problem:

https://community.spotify.com/t5/Android/Poor-Audio-Quality-When-Using-Wired-Headphones/m-p/4950944/...