The quality of the components Rock Pi S

Please tell me if any of you have problems with Rock Pi S? I already have a second Rock Pi S with problems? On the first board, NAND (4Gb) is no longer visible. The second board without NAND freezes intermittently (the blue LED stops flashing). These are already two boards out of 15 that I bought from Radxa. Now I have stopped new purchases of these boards and wondered if I should continue to make projects on this base.

Hi, @IgorKh

Did you buy the ROCK Pi S recently? Can you take a picture of the board? We updated the ROCK Pi S with rk3308bs instead of rk3308b used in previous ROCK Pi S. You should use the latest images from:

Here is a photo of 2 problematic ROCK Pi S
I bought all devices here
From the beginning, the boards worked fine, then the problems began.

This is a photo of my project based on ROCK Pi S. This is a mini server for a smart home system. More than 10 devices work for my clients and I am very worried that I will continue to have problems with ROCK Pi S

I checked again, all boards have RK3308B