Just started playing the game for the first time. Want to lower the sound effects of the game, in particular the waves and bird sounds. I find when I lower the slider, at first it seems to work. However suddenly the effect will come back loud again. In fact, I get loud and soft version of the same sound and it changes speakers. So for example, with the slider all the way down to almost the lowest end, I'll get a bird chirp in one speaker real soft, at the level the slider is at, and then soon after I'll get a loud, jarring as hell, bird chirp in another speaker, and it will just continue to oscillate like that, seeming randomly. Same with wave sounds and others. Its getting to me so much that I find I can't keep playing without fixing it. Also, if, during a loud sound, I'll slide the slider down in the middle of the sound playing and it will instantly go down with the slider, but then, sure enough, soon after I get a mega loud chirp again.

The music slider works fine.

Any ideas or solutions? Thanks.

Playing on Win 10.

I know this is old but I ran into the same issue. The underlying problem seems to be unfixable, as I have gathered by my emails with the GOG.com support. But here is a workaround for anyone who comes after us: The sound effect slider has to be set to the maximum ingame, then you can go to the Windows Volume Mixer and lower Anno 1602 from there.

This post might be old, but still relevant! This solved my sound issue after tinkering with my system for over 2 hours. Thank you very much!!!