title: Reuse of table cells issue
body: <p>I believe I am incorrectly implementing <code>cellForRowAtIndexPath</code>. I have a <code>UISlider</code> that is hidden by default and appears when a button is pressed in the table cell. When I press the button in the first cell,the slider appears not only in the first cell, but in every third  cell when I scroll down. I am currently avoiding this by reseting the slider's hidden property to <code>YES</code> in <code>cellForRowAtIndexPath</code>. I also do this for other views in the cell I need hidden by default. This creates a new issue when I scroll back up to the first cell, the slider is hidden because the property is reset in <code>cellForRowAtIndexPath</code>. This leads me to believe I'm doing something wrong. </p>
  
  <p>Here is my code:</p>
  
  <pre><code>- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
  {
  
  static NSString *CellIdentifier = @"Cell";
  
  SongsCustomCell *songCell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
  
  if (songCell == nil) {
      songCell = [[SongsCustomCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier];
      NSLog(@"new cell created");
  }
  
  NSDictionary *dictionary = [parseTrackArray objectAtIndex: indexPath.row];
  NSString *trackTitle = [dictionary objectForKey:@"trackTitle"];
  NSString *trackLink = [dictionary objectForKey:@"trackStreamLink"];
  songCell.trackLinkString = trackLink;
  songCell.trackTitleString = trackTitle;
  [songCell.trackTitleLabel setFont:[UIFont fontWithName:@"Calibri" size:22]];
  songCell.trackTitleLabel.text = [NSString stringWithFormat:@"%@", trackTitle];
  
  songCell.playButton.hidden = NO;
  songCell.playbackSlider.hidden = YES;
  songCell.playerHasLoaded = NO;
  songCell.moviePlayer.view.hidden = YES;
  
  return songCell;
  }
  </code></pre>