Hi,
I looked yesterday in kmix code and I see this, which I think is a bit
wrong, or I do not understand why close() is called even if open fails - we
just want to know if mixer is valid.

bool Mixer_Backend::isValid() {
        bool valid = false;
        int ret = open();
        if ( ret == 0  && m_mixDevices.count() > 0) {
          valid = true;
        }
        close();
        return valid;
}

regards