    //=============================================================================
    //  MuseScore
    //  Music Composition & Notation
    //
    //  Copyright (C) 2007-2011 Werner Schweer
    //
    //  This program is free software; you can redistribute it and/or modify
    //  it under the terms of the GNU General Public License version 2
    //  as published by the Free Software Foundation and appearing in
    //  the file LICENCE.GPL
    //=============================================================================

    #include "audiofile.h"

    static sf_count_t getFileLen(void* f) {
          return ((AudioFile*)f)->getFileLen();
          }
    static sf_count_t seek(sf_count_t offset, int whence, void* f) {
          return ((AudioFile*)f)->seek(offset, whence);
          }
    static sf_count_t read(void* ptr, sf_count_t count, void* f) {
          return ((AudioFile*)f)->read(ptr, count);
          }
    static sf_count_t write(const void* ptr, sf_count_t count, void* f) {
          return ((AudioFile*)f)->write(ptr, count);
          }
    static sf_count_t tell(void* f) {
          return ((AudioFile*)f)->tell();
          }

    static SF_VIRTUAL_IO sfio = {
          getFileLen,
          seek,
          read,
          write,
          tell
          };

    //---------------------------------------------------------
    //   AudioFile
    //---------------------------------------------------------

    AudioFile::AudioFile()
          {
          memset(&info, 0, sizeof(info));
          memset(&inst, 0, sizeof(inst));
          sf = 0;
          }

    AudioFile::~AudioFile()
          {
          if (sf)
                sf_close(sf);
          }

    //---------------------------------------------------------
    //   open
    //---------------------------------------------------------

    bool AudioFile::open(const QByteArray& b)
          {
          buf = b;
          idx = 0;
          sf  = sf_open_virtual(&sfio, SFM_READ, &info, this);
          hasInstrument = sf_command(sf, SFC_GET_INSTRUMENT, &inst, sizeof(inst)) == SF_TRUE;

          return sf != 0;
          }

    //---------------------------------------------------------
    //   read
    //---------------------------------------------------------

    int AudioFile::read(short* data, int frames)
          {
          return sf_readf_short(sf, data, frames);
          }

    //---------------------------------------------------------
    //   seek
    //---------------------------------------------------------

    sf_count_t AudioFile::seek(sf_count_t offset, int whence)
          {
          switch(whence) {
                case SEEK_SET:
                      idx = offset;
                      break;
                case SEEK_CUR:
                      idx += offset;
                      break;
                case SEEK_END:
                      idx = buf.size() + offset;
                      break;
                }
          return idx;
          }

    //---------------------------------------------------------
    //   read
    //---------------------------------------------------------

    sf_count_t AudioFile::read(void* ptr, sf_count_t count)
          {
          count = qMin(count, (sf_count_t)(buf.size() - idx));
          memcpy(ptr, buf.data() + idx, count);
          idx += count;
          return count;
          }

    //---------------------------------------------------------
    //   write
    //---------------------------------------------------------

    sf_count_t AudioFile::write(const void* /*ptr*/, sf_count_t /*count*/)
          {
          printf("write\n");
          return 0;
          }

↑ V730 Not all members of a class are initialized inside the constructor. Consider inspecting: hasInstrument, idx.