Blackhole 3.0.4 - GUI restarts suddenly

[Aceman]

Hello,
i have the BH 3.0.4 on board and since a couple of days,the Duo2 restarts suddenly the GUI when i am watching any channel.
Trying to solve this,i increased the fan speed,i thought maybe overheating but it occurs agin and again.Sometimes after 5 minutes,sometimes after a few seconds.
I flashed now version 3.0.4 D but same trouble.
Any ideas how to solve this?

 

[any]

and it happened to me too but I have BH ULTIMO 4K

 

[Aceman]

I notice that it happens when the decoder is on scrambled channels.Even if i use an official CI module with regular abonnement (Tivusat) it restarts suddenly after some minutes.If i watch any free channel,it stays for hours.Very strange.