I just tried Indy 4 Talkie version in ScummVM5.1, but no speech and no
music is played. Why?

I found the problem.
It seems that in ScummVM5.1 for MorphOS the sound output is hardcoded
to use the onboard chipset. But my AHI is configured to use a SB Live
card. Pretty lame, is there a way to tell ScummVM to use the proper
AHI unit instead of the onboard chipset?

Well and the music in the PC version of Indy 4 is MIDI... i hate it :)
Best would be the Amiga version with speech of PC version!

How does ScummVM work for you? Is the spped good? I've only tried it using the downloadable versions of Steel Sky and its not stable at all. It locks up and is slow. I've got a G4 too.

On another note, can I use the Amiga versions of Scumm games? I have Loom, all the monkey islands ect that I even turned into ADF files for UAE. I hear there is a tool to extract the data files you need from them, but cant find any info on how to get or use them.

@Acill:
I have a PegII G3 and I tried Maniac Mansion 2 (DOTT) and Indy 4, both "Talkie"-versions working stable and fast in ScummVM5.1!

@Bladerunner:
The screen where Indy 4 really starts (street with newspaper stand) is so freakin ugly in the PC version (big fat pixels everywhere, looks like Lego), I'm 100% sure it looked better on the Amiga. Maybe because the PC version is 320x200 and not 320x256... I really don't know but it looks awful and the MIDI sound reminds me of ringing tones on my mobile phone, but not of the nice melody I remember from the Amiga version!
There seem to be some screens that look better because of the 256 colors, but even the best interpolating algorithms can't make this PC version look good on a TFT.

Remove pegasos.audio from MOSSYS:Devs and try again.