Stamina 2.5 from rapps - plays absolutely no sound although AC97 is 'working'

0.4.11-RC-23-gb5fef42 gcc dbg linux with AC97 from rapps

I just learned from a crosstest in my WinXP SP3 VM, that Stamina 2.5 from rapps should play a lot of sound and music.
But in ReactOS it remains totally silent all the time, although I could properly play the ros start sound in mplay before and after the Stamina-test. So AC97 did work to some degree and also 'sysaudio did not suck' here.
I never had sound in this application in all tests that I did during the last years in ros.

Reproduction steps
-install AC97 and reboot like an idiot to make it finally 'work'
-install "MFC 4.2 & VB6 (Home-made)" from rapps to get MFC42.dll
-Install Stamina 2.5 from rapps
-Run the main app and hit space to run a games session, this is where some sound already should get played.
0.4.11-RC-23-gb5fef42_stamina2_5_NoSound.log

Imho the only 3sound related lines that get logged after Stamina startup are:

(drivers/ksfilter/swenum/swenum.c:314) SwDispatchCreate 0

(drivers/ksfilter/ks/swenum.c:1927) KsServiceBusEnumCreateRequest IRP B1BD0008 Name \{cd171de3-69e5-11d2-b56d-0000f8754380}&{9b365890-165f-11d0-a195-0020afd156e4}

(drivers/ksfilter/swenum/swenum.c:328) SwDispatchCreate 104

Pro-tip
The app has many .mp3 files in its app folder in 'sound' subfolder, eventually checking their format helps us to understand where we lack. VLC3.0.3 properly plays those mp3 files in ros.