XPS 13 9310, BIOS crashes in sleep, runs system diagnosis

First of all, I know that modern standby is a pain and doesn't work reliably.

Nevertheless I have an extended issue that looks more lika a BIOS issue. Every now and then when I close the lid, the laptop starts getting hot and the fans ramp up. When I open the lid again, I see a BIOS screen telling me, that "System diagnosis was successfull".

It seems like the BIOS crashes during going to S0/S1+ and starts some system diagnosis. So, basically the laptop stays there at full CPU power (speed stepping is not available in BIOS mode) and waits for the user to press "OK" or until the battery runs ot ouf power. During that, the Laptop gets extremely hot when the fans are blocked (e.g. laptop laying on a couch).

Does anyone see the same behaviour? I tend to call Dell support but I know that they will only ask me to check the drivers and reinstall windows.