MY firmware is Q554E -
TV Model is 40PFL5507H/12.

When I use Youtube APP, after 10 or 20 or 30 seconds (depending on circumstances) the APP freezes on the last photogram.
The only way to restart SMARTTV is restart TV!

All the other devices (android phone, Windows PC, LG Blueray,IPHONE) works perfectly with youtube.

My broadband is 20 Mb in upload and 1 mb in upload.

I have tried to exclude firewall or connect wired the television (instead of WI-FI), but the APP freezes with simple video or HD video.
Please Help me if possible!!!!!!!!!