I just turned on the 2nd GameShell I had to get replaced during the last 3 months, and for some reason it just shows the DEOT splash screen, (I’m using the DEOT OS obviously) and after they are displayed on the LCD the screen just shows a black empty terminal. If you press the up button for example right before the splash screen ends it shows ^]]B in the terminal (duh) and it doesn’t stop until you disconnect the battery. I have had multiple issues similar to this that I have solved, but I just can’t seem to fix this one. When I get home from vacation I will attempt to insert a SD card flashed with the standard CPI OS and see if it works then.
I am very frustrated with the quality of this product and the fact that it pretty much breaks every few months. 
Here’s a video I recorded trying to power on the GS: