PlaySoundFile("sound/c/1.rso") // works
// .. and somewhere else in the code, after time passed, and even when using ClearSounds()...
PlaySoundFile("sound/f/1.rso") // doesn't work... or plays c/1 sound instead of f/1

#pragma config(Sensor, S3, touchSensor, sensorTouch)
#pragma config(Sensor, S4, colorPort, sensorCOLORFULL)

void colorToSound();
void resetDidPlayNote();
void soundDummy();
task ButtonTask();

int scale = 1;
const int maxNotes = 6;
bool didPlayNote[maxNotes];

task main() {
    soundDummy();
    resetDidPlayNote();
    nNxtButtonTask  = ButtonTask;

    while (true) {
        if ( SensorValue(touchSensor) == 1 ) {
            colorToSound();
        }
        else {
            resetDidPlayNote();
        }
        wait1Msec(50);
    }
}

void resetDidPlayNote() {
    int i;
    for (i = 0; i < maxNotes; i++) { didPlayNote[i] = false; }
}

void colorToSound() {
    string note = "0";
    switch (SensorValue[colorPort]) {
        case BLACKCOLOR: note = "1"; break;
        case REDCOLOR: note = "2"; break;
        case GREENCOLOR: note = "3"; break;
        case YELLOWCOLOR: note = "4"; break;
        case BLUECOLOR: note = "5"; break;
        case WHITECOLOR: note = "6"; break;
    }
    int iNote = atoi(note);
    string scaleName = "c";
    switch (scale) {
        case 1: scaleName = "c"; break;
        case 2: scaleName = "f"; break;
    }

    if (iNote != 0 && !didPlayNote[iNote - 1]) {
        // PlayTone(500 + note * 100, 1);

        resetDidPlayNote();
        didPlayNote[iNote - 1] = true;

        string soundFile = "sound/";
        strcat(soundFile, scaleName);
        strcat(soundFile, "/");
        strcat(soundFile, note);
        strcat(soundFile, ".rso");

        nxtDisplayTextLine(2, "Scale %s", scaleName);
        nxtDisplayTextLine(3, "Note  %s", note);
        nxtDisplayTextLine(4, "%s", soundFile);
        ClearSounds();

        // passing soundFile as variable didn't work so far (see other thread question), hence this workaround
        if     (soundFile == "sound/c/1.rso") { PlaySoundFile("sound/c/1.rso"); }
        else if (soundFile == "sound/c/2.rso") { PlaySoundFile("sound/c/2.rso"); }
        else if (soundFile == "sound/c/3.rso") { PlaySoundFile("sound/c/3.rso"); }
        else if (soundFile == "sound/c/4.rso") { PlaySoundFile("sound/c/4.rso"); }
        else if (soundFile == "sound/c/5.rso") { PlaySoundFile("sound/c/5.rso"); }
        else if (soundFile == "sound/c/6.rso") { PlaySoundFile("sound/c/6.rso"); }

        else if (soundFile == "sound/f/1.rso") { PlaySoundFile("sound/f/1.rso"); }
        else if (soundFile == "sound/f/2.rso") { PlaySoundFile("sound/f/2.rso"); }
        else if (soundFile == "sound/f/3.rso") { PlaySoundFile("sound/f/3.rso"); }
        else if (soundFile == "sound/f/4.rso") { PlaySoundFile("sound/f/4.rso"); }
        else if (soundFile == "sound/f/5.rso") { PlaySoundFile("sound/f/5.rso"); }
        else if (soundFile == "sound/f/6.rso") { PlaySoundFile("sound/f/6.rso"); }
    }
}

task ButtonTask() {
    switch (nNxtButtonPressed) {
        // case kLeftButton: ; break;
        // case kRightButton: ; break;
        case kEnterButton:
            const int maxScales = 2;
            scale++;
            if (scale > maxScales) { scale = 1; }
            break;
   }
   return;
}

void soundDummy() {
    // PlaySoundFile("sound/c/1.rso");
}