IOS 7.1 UICollectionView not recognising full click area for drag - ios

Question

I have a UICollectionView with
a custom layout that displays the items in a horizontal row
a custom UICollectionViewCell which contains a number of subviews - an image
and some labels.
Multiple instances of the UICollectionView are displayed vertically in a UITableView.
On iOS 8.1, all works well. Testing on iOS 7.1 though I can not drag the collection unless my finger is in the top third of the row (indicated by the yellow rectangle in the picture).
Note that the UITableView scrolls correctly vertically.
Any suggestions?
Thanks in advance, and apologies for the C#.
// The Layout
public sealed class SingleRowLayout : UICollectionViewFlowLayout
{
public SingleRowLayout()
{
this.ItemSize = new CGSize(50, 120); // 120 is the full cell height
this.ScrollDirection = UICollectionViewScrollDirection.Horizontal;
}
}
// The UICollectionViewCell
public sealed class StickerViewCell : UICollectionViewCell
{
[Export ("initWithFrame:")]
public StickerViewCell (CGRect frame) : base (frame)
{
var top = 0f;
this.imageView = new UIImageView();
this.imageView.ContentMode = UIViewContentMode.ScaleAspectFit;
this.imageView.Frame = new CGRect(
new CGPoint(GridDimensions.ImageInternalSidePadding, top),
new CGSize(GridDimensions.StickerWidth - (GridDimensions.ImageInternalSidePadding * 2), GridDimensions.StickerHeight)
);
top = (float)this.imageView.Frame.Height
this.sequenceTextView = this.createTextView(ref top);
this.dateTextView = this.createTextView(ref top);
this.sensationTextView = this.createTextView(ref top);
ContentView.AddSubview(this.imageView);
ContentView.AddSubview(this.sequenceTextView);
ContentView.AddSubview(this.sensationTextView);
ContentView.AddSubview(this.dateTextView);
}
private UILabel createTextView(ref float top)
{
var result = new UILabel();
result.AdjustsFontSizeToFitWidth = true;
result.Frame = new CGRect(
new CGPoint(2, top),
new CGSize(GridDimensions.StickerWidth - (2 * 2), GridDimensions.TextHeight)
);
top += GridDimensions.TextHeight + GridDimensions.TextFieldSpacing;
return result;
}
}