Combination clickable View and NestedScrollView -> onClick is triggered on second touch - onclick

Question

I'm trying to place some clickable CardViews in a NestedScrollView (using the Material lib 22.2.1).
Most of my code seem to run without any issue (Toolbar gets collapsed, GUI is shown correctly, etc.). But when the layout gets scrolled (aka: the Toolbar gets collapsed), I have to touch 1x one clickable view, to "re-enable" the clickable-behaviour of the layout. Maybe it's unclear what I mean, so here a scenario:
app starts
fragment gets loaded
clicking a card -> onClick is triggered -> works fine
scrolling downwards (Toolbar gets collapsed now) -> works fine
clicking a card -> onClick isn't fired anymore :-/
now the layout works fine again - until the layout gets scrolled again
If anybody know what's causing this one, please let me know.
Here is some code (some parts are from a tutorial by Chris Banes)
<android.support.design.widget.CoordinatorLayout
android:id="#+id/rootLayout"
android:layout_width="match_parent"
android:layout_height="match_parent">
<android.support.design.widget.AppBarLayout
android:id="#+id/appbar"
android:layout_width="match_parent"
android:layout_height="#dimen/app_bar_height">
<android.support.design.widget.CollapsingToolbarLayout
android:id="#+id/collapsingToolbarLayout"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:contentScrim="?attr/colorPrimary"
app:expandedTitleMarginStart="#dimen/expanded_toolbar_title_margin_start"
app:layout_scrollFlags="scroll|exitUntilCollapsed"
app:layout_behavior="#string/appbar_scrolling_view_behavior">
<ImageView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:scaleType="centerCrop"
android:src="#color/purple_5"
app:layout_collapseMode="parallax"
app:layout_collapseParallaxMultiplier="0.7"/>
<android.support.v7.widget.Toolbar
android:id="#+id/toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
app:layout_collapseMode="pin"/>
</android.support.design.widget.CollapsingToolbarLayout>
</android.support.design.widget.AppBarLayout>
<android.support.v4.widget.NestedScrollView
android:id="#+id/frame"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_behavior="#string/appbar_scrolling_view_behavior"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:android="http://schemas.android.com/apk/res/android"/>
<android.support.design.widget.FloatingActionButton
android:id="#+id/fab"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_margin="#dimen/fab_margin"
android:clickable="true"
android:src="#drawable/ic_launcher"
app:layout_anchor="#+id/appbar"
app:layout_anchorGravity="bottom|right|end"
/>
</android.support.design.widget.CoordinatorLayout>
the fragments content
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:paddingTop="24dp"
xmlns:android="http://schemas.android.com/apk/res/android">
<android.support.v7.widget.CardView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_margin="#dimen/card_margin"
android:clickable="true">
<LinearLayout
style="#style/Widget.CardContent"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:clickable="false">
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Info"
android:textAppearance="#style/TextAppearance.AppCompat.Title"/>
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="#string/cheese_ipsum"/>
</LinearLayout>
</android.support.v7.widget.CardView>
<android.support.v7.widget.CardView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginBottom="#dimen/card_margin"
android:layout_marginLeft="#dimen/card_margin"
android:layout_marginRight="#dimen/card_margin"
android:clickable="true">
<LinearLayout
style="#style/Widget.CardContent"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:clickable="true">
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Friends"
android:textAppearance="#style/TextAppearance.AppCompat.Title"/>
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="#string/cheese_ipsum"/>
</LinearLayout>
</android.support.v7.widget.CardView>
<android.support.v7.widget.CardView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginBottom="#dimen/card_margin"
android:layout_marginLeft="#dimen/card_margin"
android:layout_marginRight="#dimen/card_margin"
android:clickable="true"
android:foreground="#drawable/card_foreground"
android:id="#+id/testCard">
<LinearLayout
style="#style/Widget.CardContent"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Related"
android:textAppearance="#style/TextAppearance.AppCompat.Title"/>
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="#string/cheese_ipsum"/>
</LinearLayout>
</android.support.v7.widget.CardView>
<LinearLayout
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="1000dp"/>
</LinearLayout>
setting the fragment (the 'content'):
private void makeFragmentTransaction(Fragment fragment) {
android.support.v4.app.FragmentTransaction fragmentTransaction =
getSupportFragmentManager().beginTransaction();
fragmentTransaction.replace(R.id.frame, fragment);
fragmentTransaction.commit();
}
Thanks in advance.