Mismatched volume controls of Sound Blaster X3

[buboleck]

Hello,

Recently I got Creative Sound Blaster X3 (SB1810) as it seemed it works fine with linux. I'm using Gentoo with Plasma desktop (ALSA + Pipewire) and the onboard sound is OK but the SB X3 seems is misbehaving, I found that the volume controls for RearLeft is swapped with Center and RearRight is swapped with the LFE. (Also tried live Ubuntu 24.04 same issue)

On the other hand maybe related, I was not able to get stereo upmix working in any way, ALSA upmix does not want to work as also the Pipiwire upmix.

Gentoo kernel 6.10.9
alsa-lib-1.2.12
alsa-tools-1.2.11
alsa-utils-1.2.12
alsa-plugins-1.2.12
pyalsa-1.2.12