Comment # 1 on bug 1187439 from Takashi Iwai

If it worked on Leap 15.2, please try to install the old Leap 15.2 kernel on
top of your Leap 15.3 system and confirm whether the problem is gone with that.
There are little differences regarding the MMC subsystem between Leap 15.2 and
15.3 kernels, so we may hunt down, if it's really a regression introduced by
some recent backport patches.