AIR33 NetStream StageVideo only works on simulator

There’ve been reports of problems with video playback on iOS under AIR 33.1.1.98 (eg GAMUA #211). Here’s another, different fail. The other issues relate to mp4 playback. This is for HLS formatted playlists. I’ve used the following NetStream on StageVideo code with the same videos for at least 5 years now with no problems:

var stageVideoAvail:Boolean;
var sv:StageVideo;
var nc:NetConnection = new NetConnection();
nc.connect(null);
var ns:NetStream = new NetStream(nc);
ns.addEventListener(NetStatusEvent.NET_STATUS, onStatus);
var netClient:Object = new Object();
ns.client = netClient;

function onAvail(e:StageVideoAvailabilityEvent):void {
	stageVideoAvail = (e.availability == StageVideoAvailability.AVAILABLE);
	initVideo();
}
stage.addEventListener(StageVideoAvailabilityEvent.STAGE_VIDEO_AVAILABILITY, onAvail);
function initVideo():void {
	if(stageVideoAvail) {
		sv = stage.stageVideos[0];
		sv.addEventListener(StageVideoEvent.RENDER_STATE, onRender);
		sv.attachNetStream(ns);
	} else {
		var vid:Video = new Video(1984, 1116);
		vid.x = 32;
		vid.y = 210;
		addChildAt(vid,1);
		vid.attachNetStream(ns);
	}
}
function onRender(e:StageVideoEvent):void {
	sv.viewPort = vidView;
}
//play from here
function startFLV():void {
	rotator_mc.visible = true;
	ns.play("https://video.playlist.m3u8");
}
function onStatus(e:Object):void {
	if (e.info.code == "NetStream.Play.Start" || e.info.code == "NetStream.Buffer.Full") {
		rotator_mc.visible = false;
	} else if (e.info.code == "NetStream.Buffer.Empty" && endFlag == 1) {
		rotator_mc.visible = true;
	}
}
//get video duration 
netClient.onMetaData = function(meta:Object) {
	videoDuration = meta.duration;
}

Now, on iOS 13.5 (iPad) it fails at least 9 times out of 10. The audio plays fine but I get no picture. The video are short, fixed duration (not live streams) delivered via .m3u8 playlists.

But the problem only occurs on real devices. On the Xcode simulator it always plays fine, same as ever. On simulator and devices I get all the correct netstream playback codes. I’m continuing to break it down to see what might be happening but has anyone any ideas?

I take it back. I just got results from BrowserStack. Everything plays fine. My test device must be shonky.

OK, only thing I could have said is to try with the latest version 33.1.1.190