AA2+ problem channels HD

hello Gentlemen
I have a problem with the behavior of the Amiko Alien2 + Triple with soft E2 (Hyperion 4,5 PKT). On the HD channels after a few minutes hangs tuner , with settings Audio / Video 1080i , 1080p and 720p . I have to change to 575p then it is good. No HD channels is ok . This is not the fault of the receiver on the previous sofcie (SPARK) worked all right. Please help .
thanks for any advice .

really nobody knows anything? any tips?

What is your internet? The HD channels sometimes hang on slower connections when the SD channels will be fine.