Ok, made some further testing. I haven't looked up the whole thread so there might be some issues already addressed or they are simply due to my machine with the "untested" chipset. I only have checked for the picogus yet. There might be a complete shift if further progress on the machine config ads problems to the picpgus already working on some games/demos.

I have changed the jumper to IRQ7 (which is the LPT port). Irq and DMA are still set to "1". I am not able to change the IRQ for the LPT in the Bios, I can only switch from 378 to 278 or 3BC. Perhaps that will help when I put the LPT to SCSI Adapter on that lpt1 port in order to get the external CDROM working. For the actual testing this device is not plugged in, neither configured or setup (drivers).

Changing IRQ to 7:

1. PicoGus has much less crackling to my ears.
2. BrainSlayer SB-Demos still don't work. Unreal1.0 does not work in SB (crackling) 1.1 is not tested in GUS-Mode.
3. The pinballGames (PDreams2/Fantasies/Illisions) only work in SB Mode, GUS does not work*
4. Other Pinball Games do work (Silverball, Extreme Pinball, EpicPinball)
5. Ultimate BodyBlows does work in SB und GUS but SB sounds much better (game-related, not a fault of the picogus)
6. No demo (NOON) does not work, either DOPE also does not.

*The issue seems to be that the game tells me to rely on the SET Ultrassnd but the values are perhaps wrong. There is no way to tell the sound engine where the GUS really is. Perhaps the game expects "ultra init" from the GUS 4.11 package to be loaded?
The other PinballGames have a different sound engine, they tell my that they found the variable, but I have to say no and change the values for myself. Interestingly they show IRQ11 and DMA7 as standard, perhaps that is what PDreams2/Fantasies/Illusions also get and therefore not work.

My autoexec.bat has three settings
SET BLASTER
SET ULTRASND
SET ULTRADIR

I have two batch files that change the Picogus either in GUS-Mode or SB-Mode. They are called via "call gus / call sb" before starting a game.

GUS.BAT
pgusinit /GUS
pgusinit /gusenv

SB.BAT
pgusinit /SB
pgusinit /sbenv

Example:
start.bat:
CALL GUS.BAT
SILVER

dr.zeissler wrote on Today, 21:55:

*The issue seems to be that the game tells me to rely on the SET Ultrassnd but the values are perhaps wrong.

What is your ULTRASND variable?

NeoG_ wrote on 59 minutes ago:

dr.zeissler wrote on Today, 21:55:

*The issue seems to be that the game tells me to rely on the SET Ultrassnd but the values are perhaps wrong.

What is your ULTRASND variable?

...the values the game engine thinks are wrong...the values itself are right.

The correct one: 240,7,1,1,1
The gus.bat shows me that everything is OK.

I think I better make a YT this weekend on it and link it here.

dr.zeissler wrote on 57 minutes ago:

...the values the game engine thinks are wrong...the values itself are right.

The correct one: 240,7,1,1,1
The gus.bat shows me that everything is OK.

AFAIK it should be 240,1,1,7,7

Base address (240), playback DMA (1), recording DMA (1), Ultrasound IRQ (7), SB/MIDI IRQ (7)

That explains a lot, thank you. It seems that I have overlooked the different sequence... I'll test this out. Thx!
(On the real cards I always use either 260,7,7,7,7 or 260,3,3,3,3)