I have choir notes for four voices (tenor 1, tenor 2, bass 1, bass 2) or (soprano, alto, tenor and bass). I was really delighted, when I realized, that in myrweb-export I can choose, that the volume of all voices can be set individually. It works perfectly. In web export I can also mute and unmute any voice or select solo mode for any voice. Great! - but ..
This work only, if all voices are in separate staff. If I merge voices to two staffs (tenors one staff and basses one staff) or (soprano+alto one staff and tenor+bass one staff), I can adjust the volume only by staff, not by voice or singer. This happens even though I have chosen "Each singer separately" in the export window and have associated separate singer to each voice.