Mag 256 w1 freeze IPTV all 5 second!! HELP

[Firmware]

Hello,

I have buy a New Mag 256 w1 Box, and i have Problems With IPTV.
The Box freeze All 5 seconds, i have The Buffer to 5 Sekund. I Test many many Server. My Internet very fast 50Mbit conect via Cable.
Youtube HD on the Box no Problem.
What can i do?

Thanks