Hi Andi,
I looked at your files and was surprised to see you have the identical sound hardware as myself (Realtek ALC887-VD). Here it works perfectly. One thing I notice in your testlog file is this:
----- Checking G:\CONFIG.SYS ---------------------------------------------------
ERROR: DEVICE=G:\IBMCOM\MACS\MMRE.OS2
ERROR: DEVICE=G:\IBMCOM\MACS\E100B.OS2
ERROR: DEVICE=G:\IBMCOM\MACS\E1000B.OS2
Load order violation. All MAC drivers must come after all
IFS statements and all network drivers
Maybe correcting those errors (by putting those lines at the end of CONFIG.SYS) might help?
Regards,