private void Seek(long pos)
{
if (_pos != pos)
{
if (!_rdr.BaseStream.CanSeek)
{
string msg = String.Format("Cannot rewind this input stream (from {0} to {1}).", _pos, pos);
throw new NotSupportedException(msg);
}
_rdr.BaseStream.Seek(_seekpos + (pos * _nc * (_bitsPerSample / 8)), SeekOrigin.Begin);
_pos = pos;
}
}