Higher data usage when quality set to "Basic" than "Standard" or "HQ"

I recently tried reducing my mobile data usage by changing mobile data quality from “HQ” to “Basic”.

But surprisingly my data usage actually increased (to about 500MB per hour) instead!

I decided to research (*) this issue by starting “Flow” and skipping to the next song 4 times under different mobile data quality settings and measuring mobile data usage after each song skip.

These are my findings:

Basic: 27.5MB per song on average (38, 26, 21, 25)

Standard: 5MB per song on average (8, 3, 2, 7)

HQ: 12MB per song on average (15, 8, 17, 8)

High Fidelity: 54.7MB per song on average (57, 61, 36, 65)

It seems like “Basic” is actually “HQ”, “HQ” is actually “Standard” and “Standard” is actually “Basic”.

And it seems to be a re-occurring issue because 3 other threads were created about similar issues before (but all 3 got closed without resolution so I created a new one instead)

*) I re-installed the Deezer app and cleared the song cache before performing my test. After each quality change I pressed “audio output” to confirm the change was visible under “Audio settings” which it was. I used Android’s “Mobile data usage” to track the Deezer app’s data usage rounded to 1MB. I am on Android version 9 with Deezer version 7.0.25.49