Textarea jumps when typing - iOS

I can't for the life of me figure this one out, this is running on iOS 8 Titanium 3.4

When typing in the text area within my app, it randomly jumps to the top, and then on the next character entry, jumps back to where it should be (with the cursor in view). It seems very random.

The page is set up with a scrollview with form elements inside it, the text area grows with its contents and has scrollable set to false.

here is a link to a video showing the issue: demo video

There were no event listeners attached to the scroll view or the text area, although i have tried using an on change event to trigger a 'scroll to bottom' on the scroll view, however, this doesn't work either.

<Window id="windowUpload" title="blah blah blah">
        <ScrollView id="scrollView" showVerticalScrollIndicator="true">
            <View id="fieldWrap">
                <TextField id="test" hintText="*test" />
                <View class="hr"></View>
                <TextArea id="descrip" hintText="blah blah blah" suppressReturn="false" />
            </View>
        </ScrollView>
    </Window>

"Window": {
    backgroundColor: "#eee",
    statusBarStyle: Titanium.UI.iPhone.StatusBar.LIGHT_CONTENT,
    barImage: "cf-bg.jpg",
    navTintColor: "#FFF",
    tintColor: "#FFF",
    layout: 'vertical',
    translucent: false
}
"#fieldWrap": {
    top: 15,
    left: 0,
    right: 0,
    height: Ti.UI.SIZE,
    backgroundColor: "#fff",
    layout: 'vertical'
}
"TextArea": {
    left: 7,
    right: 7,
    top: 7,
    backgroundColor: "#fff",
    color: '#333',
    font: {
        fontSize: '16dp'
    },
    tintColor: "#000",
    scrollable:false
 
}
"#scrollView": {
    width: '100%',
    contentWidth: '100%',
    contentHeight: 'auto',
    layout: 'vertical'
}