Image errors and flickering on the Nintendo Switch Lite. What could be the cause?

My wife got a new Nintendo Switch Lite for Christmas and since today suddenly graphic problems in the form of flickering and horizontal lines (picture errors) appeared on the display while playing (see picture).

She has now played the game Hyrule Warriors more often, and also during the performance. The console was sometimes overwhelmed with the graphics, which was reflected in a lower FPS rate or brief image overlaps during demanding missions.

The problem with the flickering and the horizontal lines now occurs permanently, also in other games and even in the start menu. Even after a restart, the display is still incorrect.

Is it possible that the console's "graphics card" has been damaged by the frequent "overload"?

Does any of you still have an explanation and / or has any of you (had) similar problems with the Switch Lite?

I thank you in advance.

For example

Broken display

Plug in the device loose or defective.

If it was just the image errors, I would have said that the connector to the display inside the console is defective. But you write that the game runs extremely slowly. (Unfortunately, Hyurle Warriors doesn't run that well on the Switch)

How are Animal Crossing and Zelda going, do they run normally from the FPS or also slowly?

If these also have FPS drops, I would unfortunately say that there's a defect in the cooling, GPU or RAM.

This can be an internal hardware defect or a software error. Because of the software, I would just reset the switch to its factory condition and see if the problem is solved.

Otherwise, go back to the dealer to send it in or maybe even exchange it directly.

Thank you first of all.

The lower FPS rate only occurred with Hyrule Warriors so far. The other games always ran smoothly. According to my previous research, Hyrule Warriors actually runs sometimes with lower FPS and therefore less fluidly when the fights become more demanding.

That's why I asked. So I would currently assume that the display is damaged. Fortunately, if the console was bought new, this is no break and is a guarantee case.

This morning the console appeared to be error-free again. After playing for a little longer (approx. 1/2 hour) in the test game (here Luigis Mansion 3), image overlaps and image errors again occurred in video sequences. Then the first horizontal lines appeared again in the start menu. So I would now have the assumption that it might have something to do with the cooling, since the problem only seems to appear after a certain time.

Hmm as I said, if the console was newly purchased, I would unfortunately not do anything at this point. Otherwise I would have unscrewed the thing and checked whether the heat sink is properly seated, the fan starts up and the thermal paste / pads are in good condition.