Question about Strong Leap-S3

Hi, it's the box. I have two of them in use. One constantly has no connection to the Internet. I reset it to the factory settings. It then worked for 2-3 days. Then the same thing happened again. With the 2nd box, I sometimes simply have no picture. Tested with 3-4 different devices. RMA returned to digitec with "everything works". 3-4 days later the same thing.
Conclusion. The box is bad.