Adobe Air for Flash CS6 not working well on Android cellphone

I have an App to playback RTMP live stream, it works very well on AIR SDK 4.0, but google playstore noticed me to upgrade because of OpenSSL. So I download AIR SDK 18.0, but my App does not work well now.

I am using OSMF like,

var videoSource:LightweightVideoElement = null;

var url:String = "rtmp://server/liveH3Camera/ch1";

if (videoSource == null)

{

  videoSource = new LightweightVideoElement(new StreamingURLResource(url, StreamType.LIVE));

}else

{

  videoSource.resource = new StreamingURLResource(url, StreamType.LIVE);

}

mediaPlayerSprite.media = videoSource;

addChild(mediaPlayerSprite);

On an old Samsung(GT-S7560M Android 4.0.4), everything is fine, but the same App will be black screen when first time to play and second time would be dead, no response on Samsung(SGH-1337M, Android 5.0.1).

On PC and Simulator, it woks fine.

I tried AIR 15.0 17.0,18.0，black screen and dead run. Only 4.0 works well.

It make me crazy. Anyone has any idea?

Thanks!